Add connection active, idle time to pg_stat_activity

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 55f6e3711d..c721dbc0c5 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -835,7 +835,10 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time,
+            S.idle_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index b7d0fbaefd..3e0eb963b3 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -249,6 +249,7 @@ PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
 PgStat_Counter pgStatActiveTime = 0;
 PgStat_Counter pgStatTransactionIdleTime = 0;
+PgStat_Counter pgStatTransactionIdleInTxnTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
 /* Record that's written to 2PC state file when pgstat state is persisted */
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 7229598822..7ced0f738b 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -590,9 +590,20 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+				pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+				beentry->st_active_time = pgStatActiveTime;
+		}
+		else if (beentry->st_state ==  STATE_IDLEINTRANSACTION)
+		{
+			pgstat_count_conn_txn_idle_in_txn_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_in_transaction_time = pgStatTransactionIdleInTxnTime;
+		}
 		else
+		{
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_time = pgStatTransactionIdleTime;
+		}
 	}
 
 	/*
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index ff5aedc99c..8044318533 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	33
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			values[30] = Int64GetDatum(beentry->st_active_time);
+			values[31] = Int64GetDatum(beentry->st_idle_in_transaction_time);
+			values[32] = Int64GetDatum(beentry->st_idle_time);
 		}
 		else
 		{
@@ -944,6 +948,9 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			values[30] = true;
+			values[31] = true;
+			values[32] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index d068d6532e..6f2b1a8dbd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5348,9 +5348,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,int4,int4},int4',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time,idle_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index bcd3588ea2..916764a02a 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -985,6 +985,7 @@ extern PgStat_Counter pgStatBlockWriteTime;
  */
 extern PgStat_Counter pgStatActiveTime;
 extern PgStat_Counter pgStatTransactionIdleTime;
+extern PgStat_Counter pgStatTransactionIdleInTxnTime;
 
 
 /*
@@ -1092,6 +1093,8 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatActiveTime += (n))
 #define pgstat_count_conn_txn_idle_time(n)							\
 	(pgStatTransactionIdleTime += (n))
+#define pgstat_count_conn_txn_idle_in_txn_time(n)					\
+	(pgStatTransactionIdleInTxnTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
 extern void pgstat_count_heap_update(Relation rel, bool hot);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8042b817df..063262e6ae 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	int64		st_active_time;
+	int64 		st_idle_in_transaction_time;
+	int64 		st_idle_time;
 } PgBackendStatus;
 
 

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index eb560955cd..4dfa33ffa9 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -839,7 +839,10 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time,
+            S.idle_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index b7d0fbaefd..3e0eb963b3 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -249,6 +249,7 @@ PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
 PgStat_Counter pgStatActiveTime = 0;
 PgStat_Counter pgStatTransactionIdleTime = 0;
+PgStat_Counter pgStatTransactionIdleInTxnTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
 /* Record that's written to 2PC state file when pgstat state is persisted */
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 7229598822..805cf7ae1e 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -590,9 +590,21 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+				pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+				beentry->st_active_time = pgStatActiveTime;
+		}
+		else if (beentry->st_state ==  STATE_IDLEINTRANSACTION ||
+				 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+		{
+			pgstat_count_conn_txn_idle_in_txn_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_in_transaction_time = pgStatTransactionIdleInTxnTime;
+		}
 		else
+		{
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_time = pgStatTransactionIdleTime;
+		}
 	}
 
 	/*
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index ff5aedc99c..8044318533 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	33
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			values[30] = Int64GetDatum(beentry->st_active_time);
+			values[31] = Int64GetDatum(beentry->st_idle_in_transaction_time);
+			values[32] = Int64GetDatum(beentry->st_idle_time);
 		}
 		else
 		{
@@ -944,6 +948,9 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			values[30] = true;
+			values[31] = true;
+			values[32] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index d068d6532e..6f2b1a8dbd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5348,9 +5348,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,int4,int4},int4',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time,idle_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index bcd3588ea2..916764a02a 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -985,6 +985,7 @@ extern PgStat_Counter pgStatBlockWriteTime;
  */
 extern PgStat_Counter pgStatActiveTime;
 extern PgStat_Counter pgStatTransactionIdleTime;
+extern PgStat_Counter pgStatTransactionIdleInTxnTime;
 
 
 /*
@@ -1092,6 +1093,8 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatActiveTime += (n))
 #define pgstat_count_conn_txn_idle_time(n)							\
 	(pgStatTransactionIdleTime += (n))
+#define pgstat_count_conn_txn_idle_in_txn_time(n)					\
+	(pgStatTransactionIdleInTxnTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
 extern void pgstat_count_heap_update(Relation rel, bool hot);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8042b817df..063262e6ae 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	int64		st_active_time;
+	int64 		st_idle_in_transaction_time;
+	int64 		st_idle_time;
 } PgBackendStatus;
 
 

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index eb560955cd..4dfa33ffa9 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -839,7 +839,10 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time,
+            S.idle_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index b7d0fbaefd..3e0eb963b3 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -249,6 +249,7 @@ PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
 PgStat_Counter pgStatActiveTime = 0;
 PgStat_Counter pgStatTransactionIdleTime = 0;
+PgStat_Counter pgStatTransactionIdleInTxnTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
 /* Record that's written to 2PC state file when pgstat state is persisted */
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 7229598822..2d7d3b6dce 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -577,6 +577,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 */
 	if ((beentry->st_state == STATE_RUNNING ||
 		 beentry->st_state == STATE_FASTPATH ||
+		 beentry->st_state == STATE_IDLE ||
 		 beentry->st_state == STATE_IDLEINTRANSACTION ||
 		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
 		state != beentry->st_state)
@@ -590,9 +591,21 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+				pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+				beentry->st_active_time = pgStatActiveTime;
+		}
+		else if (beentry->st_state ==  STATE_IDLEINTRANSACTION ||
+				 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+		{
+			pgstat_count_conn_txn_idle_in_txn_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_in_transaction_time = pgStatTransactionIdleInTxnTime;
+		}
 		else
+		{
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_time = pgStatTransactionIdleTime;
+		}
 	}
 
 	/*
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index ff5aedc99c..471af0db6a 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	33
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			values[30] = Int64GetDatum(beentry->st_active_time);
+			values[31] = Int64GetDatum(beentry->st_idle_in_transaction_time);
+			values[32] = Int64GetDatum(beentry->st_idle_time);
 		}
 		else
 		{
@@ -944,6 +948,9 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
+			nulls[32] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index d068d6532e..6f2b1a8dbd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5348,9 +5348,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,int4,int4},int4',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time,idle_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index bcd3588ea2..916764a02a 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -985,6 +985,7 @@ extern PgStat_Counter pgStatBlockWriteTime;
  */
 extern PgStat_Counter pgStatActiveTime;
 extern PgStat_Counter pgStatTransactionIdleTime;
+extern PgStat_Counter pgStatTransactionIdleInTxnTime;
 
 
 /*
@@ -1092,6 +1093,8 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatActiveTime += (n))
 #define pgstat_count_conn_txn_idle_time(n)							\
 	(pgStatTransactionIdleTime += (n))
+#define pgstat_count_conn_txn_idle_in_txn_time(n)					\
+	(pgStatTransactionIdleInTxnTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
 extern void pgstat_count_heap_update(Relation rel, bool hot);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8042b817df..063262e6ae 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	int64		st_active_time;
+	int64 		st_idle_in_transaction_time;
+	int64 		st_idle_time;
 } PgBackendStatus;
 
 

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index eb560955cd..4dfa33ffa9 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -839,7 +839,10 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time,
+            S.idle_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index b7d0fbaefd..84c2aba9e2 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -248,6 +248,7 @@ PgStat_Counter pgStatBlockReadTime = 0;
 PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
 PgStat_Counter pgStatActiveTime = 0;
+PgStat_Counter pgStatIdleTime = 0;
 PgStat_Counter pgStatTransactionIdleTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
@@ -1018,7 +1019,7 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 			pgLastSessionReportTime = now;
 			tsmsg->m_session_time = (PgStat_Counter) secs * 1000000 + usecs;
 			tsmsg->m_active_time = pgStatActiveTime;
-			tsmsg->m_idle_in_xact_time = pgStatTransactionIdleTime;
+			tsmsg->m_idle_in_xact_time = pgStatIdleTime;
 		}
 		else
 		{
@@ -1031,7 +1032,7 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 		pgStatBlockReadTime = 0;
 		pgStatBlockWriteTime = 0;
 		pgStatActiveTime = 0;
-		pgStatTransactionIdleTime = 0;
+		pgStatIdleTime = 0;
 	}
 	else
 	{
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 7229598822..560fa0fa0c 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -577,6 +577,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 */
 	if ((beentry->st_state == STATE_RUNNING ||
 		 beentry->st_state == STATE_FASTPATH ||
+		 beentry->st_state == STATE_IDLE ||
 		 beentry->st_state == STATE_IDLEINTRANSACTION ||
 		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
 		state != beentry->st_state)
@@ -590,9 +591,21 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
+		{
+				pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+				beentry->st_active_time = pgStatActiveTime;
+		}
+		else if (beentry->st_state ==  STATE_IDLEINTRANSACTION ||
+				 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+		{
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_transaction_idle_time = pgStatTransactionIdleTime;
+		}
+		else
+		{
+			pgstat_count_conn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_time = pgStatIdleTime;
+		}
 	}
 
 	/*
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index ff5aedc99c..4049d0679e 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	33
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			values[30] = Int64GetDatum(beentry->st_active_time);
+			values[31] = Int64GetDatum(beentry->st_transaction_idle_time);
+			values[32] = Int64GetDatum(beentry->st_idle_time);
 		}
 		else
 		{
@@ -944,6 +948,9 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
+			nulls[32] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index d068d6532e..6f2b1a8dbd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5348,9 +5348,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,int4,int4},int4',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time,idle_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index bcd3588ea2..1a7f476829 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -984,6 +984,7 @@ extern PgStat_Counter pgStatBlockWriteTime;
  * pgstat_report_activity().
  */
 extern PgStat_Counter pgStatActiveTime;
+extern PgStat_Counter pgStatIdleTime;
 extern PgStat_Counter pgStatTransactionIdleTime;
 
 
@@ -1090,7 +1091,9 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatBlockWriteTime += (n))
 #define pgstat_count_conn_active_time(n)							\
 	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
+#define pgstat_count_conn_idle_time(n)							\
+	(pgStatIdleTime += (n))
+#define pgstat_count_conn_txn_idle_time(n)					\
 	(pgStatTransactionIdleTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8042b817df..5cb001e1a4 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	int64		st_active_time;
+	int64 		st_transaction_idle_time;
+	int64 		st_idle_time;
 } PgBackendStatus;
 
 

diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index eb560955cd..4dfa33ffa9 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -839,7 +839,10 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time,
+            S.idle_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 8c166e5e16..fc5e58e06b 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -248,6 +248,7 @@ PgStat_Counter pgStatBlockReadTime = 0;
 PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
 PgStat_Counter pgStatActiveTime = 0;
+PgStat_Counter pgStatIdleTime = 0;
 PgStat_Counter pgStatTransactionIdleTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
@@ -1031,7 +1032,7 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 		pgStatBlockReadTime = 0;
 		pgStatBlockWriteTime = 0;
 		pgStatActiveTime = 0;
-		pgStatTransactionIdleTime = 0;
+		pgStatIdleTime = 0;
 	}
 	else
 	{
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 7229598822..560fa0fa0c 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -577,6 +577,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 */
 	if ((beentry->st_state == STATE_RUNNING ||
 		 beentry->st_state == STATE_FASTPATH ||
+		 beentry->st_state == STATE_IDLE ||
 		 beentry->st_state == STATE_IDLEINTRANSACTION ||
 		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
 		state != beentry->st_state)
@@ -590,9 +591,21 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
+		{
+				pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+				beentry->st_active_time = pgStatActiveTime;
+		}
+		else if (beentry->st_state ==  STATE_IDLEINTRANSACTION ||
+				 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+		{
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_transaction_idle_time = pgStatTransactionIdleTime;
+		}
+		else
+		{
+			pgstat_count_conn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			beentry->st_idle_time = pgStatIdleTime;
+		}
 	}
 
 	/*
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index e64857e540..5ec64cdd90 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	33
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			values[30] = Int64GetDatum(beentry->st_active_time);
+			values[31] = Int64GetDatum(beentry->st_transaction_idle_time);
+			values[32] = Int64GetDatum(beentry->st_idle_time);
 		}
 		else
 		{
@@ -944,6 +948,9 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
+			nulls[32] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index d068d6532e..6f2b1a8dbd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5348,9 +5348,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,int4,int4},int4',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time,idle_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index bcd3588ea2..1a7f476829 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -984,6 +984,7 @@ extern PgStat_Counter pgStatBlockWriteTime;
  * pgstat_report_activity().
  */
 extern PgStat_Counter pgStatActiveTime;
+extern PgStat_Counter pgStatIdleTime;
 extern PgStat_Counter pgStatTransactionIdleTime;
 
 
@@ -1090,7 +1091,9 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatBlockWriteTime += (n))
 #define pgstat_count_conn_active_time(n)							\
 	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
+#define pgstat_count_conn_idle_time(n)							\
+	(pgStatIdleTime += (n))
+#define pgstat_count_conn_txn_idle_time(n)					\
 	(pgStatTransactionIdleTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8042b817df..5cb001e1a4 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	int64		st_active_time;
+	int64 		st_transaction_idle_time;
+	int64 		st_idle_time;
 } PgBackendStatus;
 
 

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 62f2a3332b..25290d1260 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -967,6 +967,28 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        additional types.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>active</literal> and
+       <literal>fastpath</literal> states. This value is
+       updated when a backend switches from these states to a new state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+       and <literal>idle in transaction (aborted)</literal> states. This value is
+       updated when a backend switches from these states to a new state.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 3cb69b1f87..e349709c05 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -841,7 +841,9 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 2fecf26a2c..224422cb67 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -468,6 +468,13 @@ pgstat_beshutdown_hook(int code, Datum arg)
 
 	beentry->st_procpid = 0;	/* mark invalid */
 
+	/*
+	 * Reset per-backend counters so that accumulated values for the current
+	 * backend are not used for future backends.
+	 */
+	beentry->st_total_active_time = 0;
+	beentry->st_total_transaction_idle_time = 0;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 
 	/* so that functions can check if backend_status.c is up via MyBEEntry */
@@ -550,6 +557,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+
+			beentry->st_total_active_time = 0;
+			beentry->st_total_transaction_idle_time = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -583,16 +593,31 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
+		/*
+		 * We update per-backend st_total_active_time and st_total_transaction_idle_time
+		 * separately from pgStatActiveTime and pgStatTransactionIdleTime
+		 * used in pg_stat_database to provide per-DB statistics
+		 * because the latter values are reset to 0 once the data has been sent
+		 * to the statistics collector.
+		 */
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
+			beentry->st_total_active_time += usecs_diff;
+		}
 		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
+			beentry->st_total_transaction_idle_time += usecs_diff;
+		}
 	}
 
 	/*
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 15cb17ace4..7c2776c14c 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	32
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			/* convert to msec for display */
+			values[30] = Float8GetDatum(beentry->st_total_active_time / 1000.0) ;
+			values[31] = Float8GetDatum(beentry->st_total_transaction_idle_time / 1000.0);
 		}
 		else
 		{
@@ -944,6 +948,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index b6f689e8d1..59479b8594 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5334,9 +5334,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8217d0cb6b..96d432ce49 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* time spent in respective states in usec */
+	int64		st_total_active_time;
+	int64		st_total_transaction_idle_time;
 } PgBackendStatus;
 
 
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index d652f7b5fb..5e7ee70edd 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1764,8 +1764,10 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query_id,
     s.query,
-    s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+    s.backend_type,
+    s.active_time,
+    s.idle_in_transaction_time
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1877,7 +1879,7 @@ pg_stat_gssapi| SELECT s.pid,
     s.gss_auth AS gss_authenticated,
     s.gss_princ AS principal,
     s.gss_enc AS encrypted
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_progress_analyze| SELECT s.pid,
     s.datid,
@@ -2047,7 +2049,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_replication_slots| SELECT s.slot_name,
@@ -2081,7 +2083,7 @@ pg_stat_ssl| SELECT s.pid,
     s.ssl_client_dn AS client_dn,
     s.ssl_client_serial AS client_serial,
     s.ssl_issuer_dn AS issuer_dn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 62f2a3332b..25290d1260 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -967,6 +967,28 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        additional types.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>active</literal> and
+       <literal>fastpath</literal> states. This value is
+       updated when a backend switches from these states to a new state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+       and <literal>idle in transaction (aborted)</literal> states. This value is
+       updated when a backend switches from these states to a new state.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 3cb69b1f87..e349709c05 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -841,7 +841,9 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 2fecf26a2c..31adde5ffe 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -468,6 +468,13 @@ pgstat_beshutdown_hook(int code, Datum arg)
 
 	beentry->st_procpid = 0;	/* mark invalid */
 
+	/*
+	 * Reset per-backend counters so that accumulated values for the current
+	 * backend are not used for future backends.
+	 */
+	beentry->st_total_active_time = 0;
+	beentry->st_total_transaction_idle_time = 0;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 
 	/* so that functions can check if backend_status.c is up via MyBEEntry */
@@ -524,6 +531,8 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz start_timestamp;
 	TimestampTz current_timestamp;
 	int			len = 0;
+	int64		active_time_diff = 0;
+	int64		transaction_idle_time_diff = 0;
 
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
@@ -550,6 +559,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+
+			beentry->st_total_active_time = 0;
+			beentry->st_total_transaction_idle_time = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -583,16 +595,33 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
+		/*
+		 * We update per-backend st_total_active_time and st_total_transaction_idle_time
+		 * separately from pgStatActiveTime and pgStatTransactionIdleTime
+		 * used in pg_stat_database to provide per-DB statistics because
+		 * 1. Changing the former values implies modifying beentry and thus
+		 * have to be wrapped into PGSTAT_*_WRITE_ACTIVITY macros (see below).
+		 * 2. The latter values are reset to 0 once the data has been sent
+		 * to the statistics collector.
+		 */
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
+			active_time_diff = usecs_diff;
+		}
 		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+		{
+			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
+			transaction_idle_time_diff = usecs_diff;
+		}
 	}
 
 	/*
@@ -618,6 +647,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	beentry->st_total_active_time += active_time_diff;
+	beentry->st_total_transaction_idle_time += transaction_idle_time_diff;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 15cb17ace4..7c2776c14c 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	32
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -916,6 +916,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			/* convert to msec for display */
+			values[30] = Float8GetDatum(beentry->st_total_active_time / 1000.0) ;
+			values[31] = Float8GetDatum(beentry->st_total_transaction_idle_time / 1000.0);
 		}
 		else
 		{
@@ -944,6 +948,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index b6f689e8d1..59479b8594 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5334,9 +5334,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8217d0cb6b..96d432ce49 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* time spent in respective states in usec */
+	int64		st_total_active_time;
+	int64		st_total_transaction_idle_time;
 } PgBackendStatus;
 
 
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index d652f7b5fb..5e7ee70edd 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1764,8 +1764,10 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query_id,
     s.query,
-    s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+    s.backend_type,
+    s.active_time,
+    s.idle_in_transaction_time
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1877,7 +1879,7 @@ pg_stat_gssapi| SELECT s.pid,
     s.gss_auth AS gss_authenticated,
     s.gss_princ AS principal,
     s.gss_enc AS encrypted
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_progress_analyze| SELECT s.pid,
     s.datid,
@@ -2047,7 +2049,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_replication_slots| SELECT s.slot_name,
@@ -2081,7 +2083,7 @@ pg_stat_ssl| SELECT s.pid,
     s.ssl_client_dn AS client_dn,
     s.ssl_client_serial AS client_serial,
     s.ssl_issuer_dn AS issuer_dn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,

diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 0646f53098..27419c1851 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -249,8 +249,8 @@ static int	pgStatXactRollback = 0;
 PgStat_Counter pgStatBlockReadTime = 0;
 PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
-PgStat_Counter pgStatActiveTime = 0;
-PgStat_Counter pgStatTransactionIdleTime = 0;
+PgStat_Counter pgStatLastActiveTime = 0;
+PgStat_Counter pgStatLastTransactionIdleTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
 /* Record that's written to 2PC state file when pgstat state is persisted */
@@ -1026,8 +1026,13 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 			TimestampDifference(pgLastSessionReportTime, now, &secs, &usecs);
 			pgLastSessionReportTime = now;
 			tsmsg->m_session_time = (PgStat_Counter) secs * 1000000 + usecs;
-			tsmsg->m_active_time = pgStatActiveTime;
-			tsmsg->m_idle_in_xact_time = pgStatTransactionIdleTime;
+
+			/* send the difference since the last report */
+			tsmsg->m_active_time =
+				pgstat_get_my_active_time() - pgStatLastActiveTime;
+			tsmsg->m_idle_in_xact_time =
+				pgstat_get_my_transaction_idle_time() -
+				pgStatLastTransactionIdleTime;
 		}
 		else
 		{
@@ -1039,8 +1044,8 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 		pgStatXactRollback = 0;
 		pgStatBlockReadTime = 0;
 		pgStatBlockWriteTime = 0;
-		pgStatActiveTime = 0;
-		pgStatTransactionIdleTime = 0;
+		pgStatLastActiveTime = pgstat_get_my_active_time();
+		pgStatLastTransactionIdleTime =  pgstat_get_my_transaction_idle_time();
 	}
 	else
 	{
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 5f15dcdc05..8b6836a662 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -613,15 +613,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		 */
 		if (beentry->st_state == STATE_RUNNING ||
 			beentry->st_state == STATE_FASTPATH)
-		{
-			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
 			active_time_diff = usecs_diff;
-		}
 		else
-		{
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
 			transaction_idle_time_diff = usecs_diff;
-		}
 	}
 
 	/*
@@ -1078,6 +1072,48 @@ pgstat_get_my_query_id(void)
 }
 
 
+/* ----------
+ * pgstat_get_my_active_time() -
+ *
+ * Return current backend's accumulated active time.
+ */
+uint64
+pgstat_get_my_active_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_active_time;
+}
+
+
+/* ----------
+ * pgstat_get_my_transaction_idle_time() -
+ *
+ * Return current backend's accumulated in-transaction idel time.
+ */
+uint64
+pgstat_get_my_transaction_idle_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_transaction_idle_time;
+}
+
+
 /* ----------
  * pgstat_fetch_stat_beentry() -
  *
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index e10d20222a..382d7202c1 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -1185,10 +1185,6 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatBlockReadTime += (n))
 #define pgstat_count_buffer_write_time(n)							\
 	(pgStatBlockWriteTime += (n))
-#define pgstat_count_conn_active_time(n)							\
-	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
-	(pgStatTransactionIdleTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
 extern void pgstat_count_heap_update(Relation rel, bool hot);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 96d432ce49..1791dd6842 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -309,6 +309,8 @@ extern const char *pgstat_get_backend_current_activity(int pid, bool checkUser);
 extern const char *pgstat_get_crashed_backend_activity(int pid, char *buffer,
 													   int buflen);
 extern uint64 pgstat_get_my_query_id(void);
+extern uint64 pgstat_get_my_active_time(void);
+extern uint64 pgstat_get_my_transaction_idle_time(void);
 
 
 /* ----------

diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 8b6836a662..996f4e88d7 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -587,10 +587,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 * If the state has changed from "active" or "idle in transaction",
 	 * calculate the duration.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+	if ((PGSTAT_IS_ACTIVE(beentry) || PGSTAT_IS_IDLEINTRANSACTION(beentry)) &&
 		state != beentry->st_state)
 	{
 		long		secs;
@@ -611,8 +608,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		 * 2. The latter values are reset to 0 once the data has been sent
 		 * to the statistics collector.
 		 */
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
+		if (PGSTAT_IS_ACTIVE(beentry))
 			active_time_diff = usecs_diff;
 		else
 			transaction_idle_time_diff = usecs_diff;
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 7c2776c14c..48c0ffa33a 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -675,6 +675,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 		{
 			SockAddr	zero_clientaddr;
 			char	   *clipped_activity;
+			int64		tmp_time;
 
 			switch (beentry->st_state)
 			{
@@ -917,9 +918,25 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
 
-			/* convert to msec for display */
-			values[30] = Float8GetDatum(beentry->st_total_active_time / 1000.0) ;
-			values[31] = Float8GetDatum(beentry->st_total_transaction_idle_time / 1000.0);
+			tmp_time = beentry->st_total_active_time;
+
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_ACTIVE(beentry))
+				tmp_time +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+
+			/* convert it to msec */
+			values[30] = Float8GetDatum(tmp_time / 1000.0) ;
+
+			tmp_time = beentry->st_total_transaction_idle_time;
+
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_IDLEINTRANSACTION(beentry))
+				tmp_time +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+
+			/* convert it to msec */
+			values[31] = Float8GetDatum(tmp_time);
 		}
 		else
 		{
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 1791dd6842..a03225c4f0 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -235,6 +235,12 @@ typedef struct PgBackendStatus
 	((before_changecount) == (after_changecount) && \
 	 ((before_changecount) & 1) == 0)
 
+/* macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s)												\
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLEINTRANSACTION(s)			 \
+	((s)->st_state == STATE_IDLEINTRANSACTION ||		\
+	 (s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
 
 /* ----------
  * LocalPgBackendStatus

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 62f2a3332b..bc76016834 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -967,6 +967,26 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        additional types.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>active</literal> and
+       <literal>fastpath</literal> states.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+       and <literal>idle in transaction (aborted)</literal> states.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 3cb69b1f87..e349709c05 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -841,7 +841,9 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 0646f53098..8b84533953 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -249,8 +249,8 @@ static int	pgStatXactRollback = 0;
 PgStat_Counter pgStatBlockReadTime = 0;
 PgStat_Counter pgStatBlockWriteTime = 0;
 static PgStat_Counter pgLastSessionReportTime = 0;
-PgStat_Counter pgStatActiveTime = 0;
-PgStat_Counter pgStatTransactionIdleTime = 0;
+PgStat_Counter pgStatLastActiveTime = 0;
+PgStat_Counter pgStatLastTransactionIdleTime = 0;
 SessionEndType pgStatSessionEndCause = DISCONNECT_NORMAL;
 
 /* Record that's written to 2PC state file when pgstat state is persisted */
@@ -1026,8 +1026,12 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 			TimestampDifference(pgLastSessionReportTime, now, &secs, &usecs);
 			pgLastSessionReportTime = now;
 			tsmsg->m_session_time = (PgStat_Counter) secs * 1000000 + usecs;
-			tsmsg->m_active_time = pgStatActiveTime;
-			tsmsg->m_idle_in_xact_time = pgStatTransactionIdleTime;
+
+			/* send the difference since the last report */
+			tsmsg->m_active_time =
+				pgstat_get_my_active_time() - pgStatLastActiveTime;
+			tsmsg->m_idle_in_xact_time =
+				pgstat_get_my_transaction_idle_time() - pgStatLastTransactionIdleTime;
 		}
 		else
 		{
@@ -1039,8 +1043,8 @@ pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg, TimestampTz now)
 		pgStatXactRollback = 0;
 		pgStatBlockReadTime = 0;
 		pgStatBlockWriteTime = 0;
-		pgStatActiveTime = 0;
-		pgStatTransactionIdleTime = 0;
+		pgStatLastActiveTime = pgstat_get_my_active_time();
+		pgStatLastTransactionIdleTime = pgstat_get_my_transaction_idle_time();
 	}
 	else
 	{
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 2fecf26a2c..ccea8e3325 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -468,6 +468,13 @@ pgstat_beshutdown_hook(int code, Datum arg)
 
 	beentry->st_procpid = 0;	/* mark invalid */
 
+	/*
+	 * Reset per-backend counters so that accumulated values for the current
+	 * backend are not used for future backends.
+	 */
+	beentry->st_total_active_time = 0;
+	beentry->st_total_transaction_idle_time = 0;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 
 	/* so that functions can check if backend_status.c is up via MyBEEntry */
@@ -524,6 +531,8 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz start_timestamp;
 	TimestampTz current_timestamp;
 	int			len = 0;
+	int64		active_time_diff = 0;
+	int64		transaction_idle_time_diff = 0;
 
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
@@ -550,6 +559,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+
+			beentry->st_total_active_time = 0;
+			beentry->st_total_transaction_idle_time = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -575,24 +587,31 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 * If the state has changed from "active" or "idle in transaction",
 	 * calculate the duration.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+	if ((PGSTAT_IS_ACTIVE(beentry) || PGSTAT_IS_IDLEINTRANSACTION(beentry)) &&
 		state != beentry->st_state)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		/*
+		 * We update per-backend st_total_active_time and st_total_transaction_idle_time
+		 * separately from pgStatActiveTime and pgStatTransactionIdleTime
+		 * used in pg_stat_database to provide per-DB statistics because
+		 * 1. Changing the former values implies modifying beentry and thus
+		 * have to be wrapped into PGSTAT_*_WRITE_ACTIVITY macros (see below).
+		 * 2. The latter values are reset to 0 once the data has been sent
+		 * to the statistics collector.
+		 */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			active_time_diff = usecs_diff;
 		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			transaction_idle_time_diff = usecs_diff;
 	}
 
 	/*
@@ -618,6 +637,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	beentry->st_total_active_time += active_time_diff;
+	beentry->st_total_transaction_idle_time += transaction_idle_time_diff;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
@@ -1046,6 +1068,48 @@ pgstat_get_my_query_id(void)
 }
 
 
+/* ----------
+ * pgstat_get_my_active_time() -
+ *
+ * Return current backend's accumulated active time.
+ */
+uint64
+pgstat_get_my_active_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_active_time;
+}
+
+
+/* ----------
+ * pgstat_get_my_transaction_idle_time() -
+ *
+ * Return current backend's accumulated in-transaction idle time.
+ */
+uint64
+pgstat_get_my_transaction_idle_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_transaction_idle_time;
+}
+
+
 /* ----------
  * pgstat_fetch_stat_beentry() -
  *
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 15cb17ace4..076fa1f049 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -567,7 +567,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	32
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -675,6 +675,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 		{
 			SockAddr	zero_clientaddr;
 			char	   *clipped_activity;
+			int64		time_to_report;
 
 			switch (beentry->st_state)
 			{
@@ -916,6 +917,23 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			time_to_report = beentry->st_total_active_time;
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_ACTIVE(beentry))
+				time_to_report +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+			/* convert it to msec */
+			values[30] = Float8GetDatum(time_to_report / 1000.0) ;
+
+			time_to_report = beentry->st_total_transaction_idle_time;
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_IDLEINTRANSACTION(beentry))
+				time_to_report +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+
+			/* convert it to msec */
+			values[31] = Float8GetDatum(time_to_report / 1000.0);
 		}
 		else
 		{
@@ -944,6 +962,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index b6f689e8d1..59479b8594 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5334,9 +5334,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index e10d20222a..2f168cbdab 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -1071,13 +1071,6 @@ extern PgStat_MsgWal WalStats;
 extern PgStat_Counter pgStatBlockReadTime;
 extern PgStat_Counter pgStatBlockWriteTime;
 
-/*
- * Updated by pgstat_count_conn_*_time macros, called by
- * pgstat_report_activity().
- */
-extern PgStat_Counter pgStatActiveTime;
-extern PgStat_Counter pgStatTransactionIdleTime;
-
 
 /*
  * Updated by the traffic cop and in errfinish()
@@ -1185,10 +1178,6 @@ extern void pgstat_initstats(Relation rel);
 	(pgStatBlockReadTime += (n))
 #define pgstat_count_buffer_write_time(n)							\
 	(pgStatBlockWriteTime += (n))
-#define pgstat_count_conn_active_time(n)							\
-	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
-	(pgStatTransactionIdleTime += (n))
 
 extern void pgstat_count_heap_insert(Relation rel, PgStat_Counter n);
 extern void pgstat_count_heap_update(Relation rel, bool hot);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 8217d0cb6b..e06f2c4022 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* time spent in respective states in usec */
+	int64		st_total_active_time;
+	int64		st_total_transaction_idle_time;
 } PgBackendStatus;
 
 
@@ -231,6 +235,12 @@ typedef struct PgBackendStatus
 	((before_changecount) == (after_changecount) && \
 	 ((before_changecount) & 1) == 0)
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION || \
+	 (s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
 
 /* ----------
  * LocalPgBackendStatus
@@ -305,6 +315,8 @@ extern const char *pgstat_get_backend_current_activity(int pid, bool checkUser);
 extern const char *pgstat_get_crashed_backend_activity(int pid, char *buffer,
 													   int buflen);
 extern uint64 pgstat_get_my_query_id(void);
+extern uint64 pgstat_get_my_active_time(void);
+extern uint64 pgstat_get_my_transaction_idle_time(void);
 
 
 /* ----------
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index d652f7b5fb..5e7ee70edd 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1764,8 +1764,10 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query_id,
     s.query,
-    s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+    s.backend_type,
+    s.active_time,
+    s.idle_in_transaction_time
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1877,7 +1879,7 @@ pg_stat_gssapi| SELECT s.pid,
     s.gss_auth AS gss_authenticated,
     s.gss_princ AS principal,
     s.gss_enc AS encrypted
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_progress_analyze| SELECT s.pid,
     s.datid,
@@ -2047,7 +2049,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_replication_slots| SELECT s.slot_name,
@@ -2081,7 +2083,7 @@ pg_stat_ssl| SELECT s.pid,
     s.ssl_client_dn AS client_dn,
     s.ssl_client_serial AS client_serial,
     s.ssl_issuer_dn AS issuer_dn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 4549c2560e..cf00685c96 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -979,6 +979,26 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        additional types.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>active</literal> and
+       <literal>fastpath</literal> states.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+       and <literal>idle in transaction (aborted)</literal> states.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index fedaed533b..06cea5f01c 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -864,7 +864,9 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.active_time,
+            S.idle_in_transaction_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index c7ed1e6d7a..dbb7a0aec6 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -468,6 +468,13 @@ pgstat_beshutdown_hook(int code, Datum arg)
 
 	beentry->st_procpid = 0;	/* mark invalid */
 
+	/*
+	 * Reset per-backend counters so that accumulated values for the current
+	 * backend are not used for future backends.
+	 */
+	beentry->st_total_active_time = 0;
+	beentry->st_total_transaction_idle_time = 0;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 
 	/* so that functions can check if backend_status.c is up via MyBEEntry */
@@ -524,6 +531,8 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz start_timestamp;
 	TimestampTz current_timestamp;
 	int			len = 0;
+	int64		active_time_diff = 0;
+	int64		transaction_idle_time_diff = 0;
 
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
@@ -550,6 +559,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+
+			beentry->st_total_active_time = 0;
+			beentry->st_total_transaction_idle_time = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -575,24 +587,31 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 * If the state has changed from "active" or "idle in transaction",
 	 * calculate the duration.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+	if ((PGSTAT_IS_ACTIVE(beentry) || PGSTAT_IS_IDLEINTRANSACTION(beentry)) &&
 		state != beentry->st_state)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		/*
+		 * We update per-backend st_total_active_time and st_total_transaction_idle_time
+		 * separately from pgStatActiveTime and pgStatTransactionIdleTime
+		 * used in pg_stat_database to provide per-DB statistics because
+		 * 1. Changing the former values implies modifying beentry and thus
+		 * have to be wrapped into PGSTAT_*_WRITE_ACTIVITY macros (see below).
+		 * 2. The latter values are reset to 0 once the data has been sent
+		 * to the statistics collector.
+		 */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			active_time_diff = usecs_diff;
 		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			transaction_idle_time_diff = usecs_diff;
 	}
 
 	/*
@@ -618,6 +637,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	beentry->st_total_active_time += active_time_diff;
+	beentry->st_total_transaction_idle_time += transaction_idle_time_diff;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
@@ -1046,6 +1068,48 @@ pgstat_get_my_query_id(void)
 }
 
 
+/* ----------
+ * pgstat_get_my_active_time() -
+ *
+ * Return current backend's accumulated active time.
+ */
+uint64
+pgstat_get_my_active_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_active_time;
+}
+
+
+/* ----------
+ * pgstat_get_my_transaction_idle_time() -
+ *
+ * Return current backend's accumulated in-transaction idle time.
+ */
+uint64
+pgstat_get_my_transaction_idle_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_transaction_idle_time;
+}
+
+
 /* ----------
  * pgstat_fetch_stat_beentry() -
  *
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..12c89c34cf 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -539,7 +539,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	32
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -621,6 +621,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 		{
 			SockAddr	zero_clientaddr;
 			char	   *clipped_activity;
+			int64		time_to_report;
 
 			switch (beentry->st_state)
 			{
@@ -862,6 +863,22 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			time_to_report = beentry->st_total_active_time;
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_ACTIVE(beentry))
+				time_to_report +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+			/* convert it to msec */
+			values[30] = Float8GetDatum(time_to_report / 1000.0);
+
+			time_to_report = beentry->st_total_transaction_idle_time;
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_IDLEINTRANSACTION(beentry))
+				time_to_report +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+			/* convert it to msec */
+			values[31] = Float8GetDatum(time_to_report / 1000.0);
 		}
 		else
 		{
@@ -890,6 +907,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
 		}
 
 		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 87aa571a33..795130c1c2 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5340,9 +5340,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,active_time,idle_in_transaction_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index ac28f813b4..8248e63931 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -469,10 +469,6 @@ extern void pgstat_report_connect(Oid dboid);
 	(pgStatBlockReadTime += (n))
 #define pgstat_count_buffer_write_time(n)							\
 	(pgStatBlockWriteTime += (n))
-#define pgstat_count_conn_active_time(n)							\
-	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
-	(pgStatTransactionIdleTime += (n))
 
 extern PgStat_StatDBEntry *pgstat_fetch_stat_dbentry(Oid dbid);
 
@@ -673,12 +669,6 @@ extern PGDLLIMPORT PgStat_CheckpointerStats PendingCheckpointerStats;
 extern PGDLLIMPORT PgStat_Counter pgStatBlockReadTime;
 extern PGDLLIMPORT PgStat_Counter pgStatBlockWriteTime;
 
-/*
- * Updated by pgstat_count_conn_*_time macros, called by
- * pgstat_report_activity().
- */
-extern PGDLLIMPORT PgStat_Counter pgStatActiveTime;
-extern PGDLLIMPORT PgStat_Counter pgStatTransactionIdleTime;
 
 /* updated by the traffic cop and in errfinish() */
 extern PGDLLIMPORT SessionEndType pgStatSessionEndCause;
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 7403bca25e..23660753fe 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* time spent in respective states in usec */
+	int64		st_total_active_time;
+	int64		st_total_transaction_idle_time;
 } PgBackendStatus;
 
 
@@ -231,6 +235,12 @@ typedef struct PgBackendStatus
 	((before_changecount) == (after_changecount) && \
 	 ((before_changecount) & 1) == 0)
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION || \
+	 (s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
 
 /* ----------
  * LocalPgBackendStatus
@@ -305,6 +315,8 @@ extern const char *pgstat_get_backend_current_activity(int pid, bool checkUser);
 extern const char *pgstat_get_crashed_backend_activity(int pid, char *buffer,
 													   int buflen);
 extern uint64 pgstat_get_my_query_id(void);
+extern uint64 pgstat_get_my_active_time(void);
+extern uint64 pgstat_get_my_transaction_idle_time(void);
 
 
 /* ----------
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index fc3cde3226..92174235f3 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1757,8 +1757,10 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query_id,
     s.query,
-    s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+    s.backend_type,
+    s.active_time,
+    s.idle_in_transaction_time
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1870,7 +1872,7 @@ pg_stat_gssapi| SELECT s.pid,
     s.gss_auth AS gss_authenticated,
     s.gss_princ AS principal,
     s.gss_enc AS encrypted
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_progress_analyze| SELECT s.pid,
     s.datid,
@@ -2051,7 +2053,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_replication_slots| SELECT s.slot_name,
@@ -2085,7 +2087,7 @@ pg_stat_ssl| SELECT s.pid,
     s.ssl_client_dn AS client_dn,
     s.ssl_client_serial AS client_serial,
     s.ssl_issuer_dn AS issuer_dn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, active_time, idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 4549c2560e..a0384fd3a5 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -979,6 +979,26 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        additional types.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>active</literal> and
+       <literal>fastpath</literal> states.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+       and <literal>idle in transaction (aborted)</literal> states.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index fedaed533b..3498ea874a 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -864,7 +864,9 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.total_active_time,
+            S.total_idle_in_transaction_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index c7ed1e6d7a..27285cb27d 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -336,6 +336,8 @@ pgstat_bestart(void)
 	lbeentry.st_activity_start_timestamp = 0;
 	lbeentry.st_state_start_timestamp = 0;
 	lbeentry.st_xact_start_timestamp = 0;
+	lbeentry.st_total_active_time = 0;
+	lbeentry.st_total_transaction_idle_time = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
 	/* We have userid for client-backends, wal-sender and bgworker processes */
@@ -524,6 +526,8 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz start_timestamp;
 	TimestampTz current_timestamp;
 	int			len = 0;
+	int64		active_time_diff = 0;
+	int64		transaction_idle_time_diff = 0;
 
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
@@ -550,6 +554,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+
+			beentry->st_total_active_time = 0;
+			beentry->st_total_transaction_idle_time = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -575,24 +582,31 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 * If the state has changed from "active" or "idle in transaction",
 	 * calculate the duration.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+	if ((PGSTAT_IS_ACTIVE(beentry) || PGSTAT_IS_IDLEINTRANSACTION(beentry)) &&
 		state != beentry->st_state)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		/*
+		 * We update per-backend st_total_active_time and st_total_transaction_idle_time
+		 * separately from pgStatActiveTime and pgStatTransactionIdleTime
+		 * used in pg_stat_database to provide per-DB statistics because
+		 * 1. Changing the former values implies modifying beentry and thus
+		 * have to be wrapped into PGSTAT_*_WRITE_ACTIVITY macros (see below).
+		 * 2. The latter values are reset to 0 once the data has been sent
+		 * to the statistics collector.
+		 */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			active_time_diff = usecs_diff;
 		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			transaction_idle_time_diff = usecs_diff;
 	}
 
 	/*
@@ -618,6 +632,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	beentry->st_total_active_time += active_time_diff;
+	beentry->st_total_transaction_idle_time += transaction_idle_time_diff;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
@@ -1046,6 +1063,48 @@ pgstat_get_my_query_id(void)
 }
 
 
+/* ----------
+ * pgstat_get_my_active_time() -
+ *
+ * Return current backend's accumulated active time.
+ */
+uint64
+pgstat_get_my_active_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_active_time;
+}
+
+
+/* ----------
+ * pgstat_get_my_transaction_idle_time() -
+ *
+ * Return current backend's accumulated in-transaction idle time.
+ */
+uint64
+pgstat_get_my_transaction_idle_time(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/*
+	 * There's no need for a lock around pgstat_begin_read_activity /
+	 * pgstat_end_read_activity here as it's only called from
+	 * pg_stat_get_activity which is already protected, or from the same
+	 * backend which means that there won't be concurrent writes.
+	 */
+	return MyBEEntry->st_total_transaction_idle_time;
+}
+
+
 /* ----------
  * pgstat_fetch_stat_beentry() -
  *
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..17685c1ab8 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -539,7 +539,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	32
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -621,6 +621,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 		{
 			SockAddr	zero_clientaddr;
 			char	   *clipped_activity;
+			int64		total_time_to_report;
 
 			switch (beentry->st_state)
 			{
@@ -862,6 +863,22 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			total_time_to_report = beentry->st_total_active_time;
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_ACTIVE(beentry))
+				total_time_to_report +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+			/* convert it to msec */
+			values[30] = Float8GetDatum(total_time_to_report / 1000.0) ;
+
+			total_time_to_report = beentry->st_total_transaction_idle_time;
+			/* add the realtime value to the counter if needed */
+			if (PGSTAT_IS_IDLEINTRANSACTION(beentry))
+				total_time_to_report +=
+					GetCurrentTimestamp() - beentry->st_state_start_timestamp;
+			/* convert it to msec */
+			values[31] = Float8GetDatum(total_time_to_report / 1000.0);
 		}
 		else
 		{
@@ -890,6 +907,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
 		}
 
 		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 2e41f4d9e8..bcd106897e 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5340,9 +5340,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,total_active_time,total_idle_in_transaction_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index ac28f813b4..8248e63931 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -469,10 +469,6 @@ extern void pgstat_report_connect(Oid dboid);
 	(pgStatBlockReadTime += (n))
 #define pgstat_count_buffer_write_time(n)							\
 	(pgStatBlockWriteTime += (n))
-#define pgstat_count_conn_active_time(n)							\
-	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
-	(pgStatTransactionIdleTime += (n))
 
 extern PgStat_StatDBEntry *pgstat_fetch_stat_dbentry(Oid dbid);
 
@@ -673,12 +669,6 @@ extern PGDLLIMPORT PgStat_CheckpointerStats PendingCheckpointerStats;
 extern PGDLLIMPORT PgStat_Counter pgStatBlockReadTime;
 extern PGDLLIMPORT PgStat_Counter pgStatBlockWriteTime;
 
-/*
- * Updated by pgstat_count_conn_*_time macros, called by
- * pgstat_report_activity().
- */
-extern PGDLLIMPORT PgStat_Counter pgStatActiveTime;
-extern PGDLLIMPORT PgStat_Counter pgStatTransactionIdleTime;
 
 /* updated by the traffic cop and in errfinish() */
 extern PGDLLIMPORT SessionEndType pgStatSessionEndCause;
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 7403bca25e..23660753fe 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* time spent in respective states in usec */
+	int64		st_total_active_time;
+	int64		st_total_transaction_idle_time;
 } PgBackendStatus;
 
 
@@ -231,6 +235,12 @@ typedef struct PgBackendStatus
 	((before_changecount) == (after_changecount) && \
 	 ((before_changecount) & 1) == 0)
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION || \
+	 (s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
 
 /* ----------
  * LocalPgBackendStatus
@@ -305,6 +315,8 @@ extern const char *pgstat_get_backend_current_activity(int pid, bool checkUser);
 extern const char *pgstat_get_crashed_backend_activity(int pid, char *buffer,
 													   int buflen);
 extern uint64 pgstat_get_my_query_id(void);
+extern uint64 pgstat_get_my_active_time(void);
+extern uint64 pgstat_get_my_transaction_idle_time(void);
 
 
 /* ----------
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 7ec3d2688f..4c9f5f8369 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1758,8 +1758,10 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query_id,
     s.query,
-    s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+    s.backend_type,
+    s.total_active_time,
+    s.total_idle_in_transaction_time
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1871,7 +1873,7 @@ pg_stat_gssapi| SELECT s.pid,
     s.gss_auth AS gss_authenticated,
     s.gss_princ AS principal,
     s.gss_enc AS encrypted
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_progress_analyze| SELECT s.pid,
     s.datid,
@@ -2052,7 +2054,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_replication_slots| SELECT s.slot_name,
@@ -2086,7 +2088,7 @@ pg_stat_ssl| SELECT s.pid,
     s.ssl_client_dn AS client_dn,
     s.ssl_client_serial AS client_serial,
     s.ssl_issuer_dn AS issuer_dn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,

From b5298301a3f5223bd78c519ddcddbd1bec9cf000 Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Wed, 20 Apr 2022 23:47:37 +0200
Subject: [PATCH] pg_stat_activity: add 'total_active_time' and
 'total_idle_in_transaction_time'

catversion bump because of the change in the contents of pg_stat_activity

Author: Sergey Dudoladov, based on the initial version by Rafia Sabih

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, and Atsushi Torikoshi

Discussion: https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 20 +++++++++++++
 src/backend/catalog/system_views.sql        |  4 ++-
 src/backend/utils/activity/backend_status.c | 33 ++++++++++++++++-----
 src/backend/utils/adt/pgstatfuncs.c         |  8 ++++-
 src/include/catalog/pg_proc.dat             |  6 ++--
 src/include/pgstat.h                        | 10 -------
 src/include/utils/backend_status.h          | 10 +++++++
 src/test/regress/expected/rules.out         | 12 ++++----
 8 files changed, 75 insertions(+), 28 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 7dbbab6f5c..943927fe34 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -979,6 +979,26 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        additional types.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>active</literal> and
+       <literal>fastpath function call</literal> states.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+       and <literal>idle in transaction (aborted)</literal> states.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index f369b1fc14..2ec6ea2304 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -864,7 +864,9 @@ CREATE VIEW pg_stat_activity AS
             s.backend_xmin,
             S.query_id,
             S.query,
-            S.backend_type
+            S.backend_type,
+            S.total_active_time,
+            S.total_idle_in_transaction_time
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index c7ed1e6d7a..8fe2929fba 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -336,6 +336,8 @@ pgstat_bestart(void)
 	lbeentry.st_activity_start_timestamp = 0;
 	lbeentry.st_state_start_timestamp = 0;
 	lbeentry.st_xact_start_timestamp = 0;
+	lbeentry.st_total_active_time = 0;
+	lbeentry.st_total_transaction_idle_time = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
 	/* We have userid for client-backends, wal-sender and bgworker processes */
@@ -524,6 +526,8 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz start_timestamp;
 	TimestampTz current_timestamp;
 	int			len = 0;
+	int64		active_time_diff = 0;
+	int64		transaction_idle_time_diff = 0;
 
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
@@ -550,6 +554,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+
+			beentry->st_total_active_time = 0;
+			beentry->st_total_transaction_idle_time = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -575,24 +582,31 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 * If the state has changed from "active" or "idle in transaction",
 	 * calculate the duration.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+	if ((PGSTAT_IS_ACTIVE(beentry) || PGSTAT_IS_IDLEINTRANSACTION(beentry)) &&
 		state != beentry->st_state)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+		/*
+		 * We update per-backend st_total_active_time and st_total_transaction_idle_time
+		 * separately from pgStatActiveTime and pgStatTransactionIdleTime
+		 * used in pg_stat_database to provide per-DB statistics because
+		 * 1. Changing the former values implies modifying beentry and thus
+		 * have to be wrapped into PGSTAT_*_WRITE_ACTIVITY macros (see below).
+		 * 2. The latter values are reset to 0 once the data has been sent
+		 * to the statistics collector.
+		 */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			active_time_diff = usecs_diff;
 		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+			transaction_idle_time_diff = usecs_diff;
 	}
 
 	/*
@@ -618,6 +632,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	beentry->st_total_active_time += active_time_diff;
+	beentry->st_total_transaction_idle_time += transaction_idle_time_diff;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index d9e2a79382..a213211f6a 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -536,7 +536,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	30
+#define PG_STAT_GET_ACTIVITY_COLS	32
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -856,6 +856,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[29] = true;
 			else
 				values[29] = UInt64GetDatum(beentry->st_query_id);
+
+			/* convert to msec */
+			values[30] = Float8GetDatum(beentry->st_total_active_time / 1000.0);
+			values[31] = Float8GetDatum(beentry->st_total_transaction_idle_time / 1000.0);
 		}
 		else
 		{
@@ -884,6 +888,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[27] = true;
 			nulls[28] = true;
 			nulls[29] = true;
+			nulls[30] = true;
+			nulls[31] = true;
 		}
 
 		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 2e41f4d9e8..bcd106897e 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5340,9 +5340,9 @@
   proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
   proretset => 't', provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'int4',
-  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+  proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,total_active_time,total_idle_in_transaction_time}',
   prosrc => 'pg_stat_get_activity' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index ac28f813b4..8248e63931 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -469,10 +469,6 @@ extern void pgstat_report_connect(Oid dboid);
 	(pgStatBlockReadTime += (n))
 #define pgstat_count_buffer_write_time(n)							\
 	(pgStatBlockWriteTime += (n))
-#define pgstat_count_conn_active_time(n)							\
-	(pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n)							\
-	(pgStatTransactionIdleTime += (n))
 
 extern PgStat_StatDBEntry *pgstat_fetch_stat_dbentry(Oid dbid);
 
@@ -673,12 +669,6 @@ extern PGDLLIMPORT PgStat_CheckpointerStats PendingCheckpointerStats;
 extern PGDLLIMPORT PgStat_Counter pgStatBlockReadTime;
 extern PGDLLIMPORT PgStat_Counter pgStatBlockWriteTime;
 
-/*
- * Updated by pgstat_count_conn_*_time macros, called by
- * pgstat_report_activity().
- */
-extern PGDLLIMPORT PgStat_Counter pgStatActiveTime;
-extern PGDLLIMPORT PgStat_Counter pgStatTransactionIdleTime;
 
 /* updated by the traffic cop and in errfinish() */
 extern PGDLLIMPORT SessionEndType pgStatSessionEndCause;
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 7403bca25e..c904714c17 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* time spent in respective states in usec */
+	int64		st_total_active_time;
+	int64		st_total_transaction_idle_time;
 } PgBackendStatus;
 
 
@@ -231,6 +235,12 @@ typedef struct PgBackendStatus
 	((before_changecount) == (after_changecount) && \
 	 ((before_changecount) & 1) == 0)
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION || \
+	 (s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
 
 /* ----------
  * LocalPgBackendStatus
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 7ec3d2688f..4c9f5f8369 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1758,8 +1758,10 @@ pg_stat_activity| SELECT s.datid,
     s.backend_xmin,
     s.query_id,
     s.query,
-    s.backend_type
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+    s.backend_type,
+    s.total_active_time,
+    s.total_idle_in_transaction_time
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1871,7 +1873,7 @@ pg_stat_gssapi| SELECT s.pid,
     s.gss_auth AS gss_authenticated,
     s.gss_princ AS principal,
     s.gss_enc AS encrypted
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_progress_analyze| SELECT s.pid,
     s.datid,
@@ -2052,7 +2054,7 @@ pg_stat_replication| SELECT s.pid,
     w.sync_priority,
     w.sync_state,
     w.reply_time
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_replication_slots| SELECT s.slot_name,
@@ -2086,7 +2088,7 @@ pg_stat_ssl| SELECT s.pid,
     s.ssl_client_dn AS client_dn,
     s.ssl_client_serial AS client_serial,
     s.ssl_issuer_dn AS issuer_dn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
   WHERE (s.client_port IS NOT NULL);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,
-- 
2.32.0

From 31f781ecd69fc42aaadd9bcdbebaf8f72449946c Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Tue, 22 Nov 2022 09:23:32 +0100
Subject: [PATCH] Add pg_stat_session

Author: Sergey Dudoladov

Adds pg_stat_session view to track statistics accumulated during
 lifetime of a session.

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, and Atsushi
Torikoshi

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 153 ++++++++++++++++++++
 src/backend/catalog/system_views.sql        |  15 ++
 src/backend/utils/activity/backend_status.c |  58 ++++++--
 src/backend/utils/adt/pgstatfuncs.c         |  70 +++++++++
 src/include/catalog/pg_proc.dat             |   9 ++
 src/include/utils/backend_status.h          |  37 +++++
 src/test/regress/expected/rules.out         |  12 ++
 7 files changed, 345 insertions(+), 9 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 1756f1a4b6..38cc29810a 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -414,6 +414,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        See <xref linkend='copy-progress-reporting'/>.
       </entry>
      </row>
+
+     <row>
+      <entry>
+       <structname>pg_stat_session</structname>
+       <indexterm><primary>pg_stat_session</primary></indexterm>
+      </entry>
+      <entry>
+       One row per server process, showing information related to
+       the currently accumulated activity of that process, such as time spent in
+       a certain state.
+       See <link linkend="monitoring-pg-stat-session-view">
+       <structname>pg_stat_session</structname></link> for details.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
@@ -5315,6 +5329,129 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
    </tgroup>
   </table>
 
+  <table id="monitoring-pg-stat-session-view" xreflabel="pg_stat_session">
+   <title><structname>pg_stat_session</structname> View</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>pid</structfield> <type>integer</type>
+      </para>
+      <para>
+       Process ID of this backend.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_running_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>running</literal> state.
+      </para></entry>
+     </row>
+
+    <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_running_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>running</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_aborted_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction (aborted)</literal> 
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_aborted_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_fastpath_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_fastpath_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>fastpath</literal>
+       state.
+      </para></entry>
+     </row>
+
+    </tbody>
+   </tgroup>
+  </table>
+
  </sect2>
 
  <sect2 id="monitoring-stats-functions">
@@ -5382,6 +5519,22 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_get_session</primary>
+        </indexterm>
+        <function>pg_stat_get_session</function> ( <type>integer</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Returns a record of information about the backend with the specified
+        process ID, or one record for each active backend in the system
+        if <literal>NULL</literal> is specified.  The fields returned are a
+        subset of those in the <structname>pg_stat_session</structname> view.
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 8608e3fa5b..8f68a6ea00 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -870,6 +870,21 @@ CREATE VIEW pg_stat_activity AS
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
 
+CREATE VIEW pg_stat_session AS
+    SELECT
+            s.pid,
+            s.total_running_time,
+            s.total_running_count,
+            s.total_idle_time,
+            s.total_idle_count,
+            s.total_transaction_idle_time,
+            s.total_transaction_idle_count,
+            s.total_transaction_idle_aborted_time,
+            s.total_transaction_idle_aborted_count,
+            s.total_fastpath_time,
+            s.total_fastpath_count
+     FROM pg_stat_get_session(NULL) as s;
+
 CREATE VIEW pg_stat_replication AS
     SELECT
             S.pid,
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 608d01ea0d..804b91cf9f 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -338,6 +338,8 @@ pgstat_bestart(void)
 	lbeentry.st_xact_start_timestamp = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
+	MemSet(&lbeentry.st_session, 0, sizeof(lbeentry.st_session));
+
 	/* We have userid for client-backends, wal-sender and bgworker processes */
 	if (lbeentry.st_backendType == B_BACKEND
 		|| lbeentry.st_backendType == B_WAL_SENDER
@@ -525,6 +527,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz current_timestamp;
 	int			len = 0;
 
+	PgBackendSessionStatus st_session_diff;
+	MemSet(&st_session_diff, 0, sizeof(st_session_diff));
+
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
 	if (!beentry)
@@ -550,6 +555,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+			MemSet(&beentry->st_session, 0, sizeof(beentry->st_session));
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -572,27 +578,46 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	current_timestamp = GetCurrentTimestamp();
 
 	/*
-	 * If the state has changed from "active" or "idle in transaction",
-	 * calculate the duration.
+	 * If the state has changed, update per-database and per-session counters.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+	if ((PGSTAT_IS_ACTIVE(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry) || 
+		 PGSTAT_IS_IDLE(beentry)) &&
 		state != beentry->st_state)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
+		/* Keep statistics for pg_stat_database intact */
+		if (PGSTAT_IS_ACTIVE(beentry))
 			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
+		else if (PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+				 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry))
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+
+		if (PGSTAT_IS_RUNNING(beentry)) {
+			st_session_diff.total_running_time = usecs_diff;
+			st_session_diff.total_running_count += 1;
+		} else if (PGSTAT_IS_IDLE(beentry)){
+			st_session_diff.total_idle_time = usecs_diff;
+			st_session_diff.total_idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION(beentry)){
+			st_session_diff.total_transaction_idle_time = usecs_diff;
+			st_session_diff.total_transaction_idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry)){
+			st_session_diff.total_transaction_idle_aborted_time = usecs_diff;
+			st_session_diff.total_transaction_idle_aborted_count += 1;
+		} else if (PGSTAT_IS_FASTPATH(beentry)){
+			st_session_diff.total_fastpath_time = usecs_diff;
+			st_session_diff.total_fastpath_count += 1;
+		}
 	}
 
 	/*
@@ -618,6 +643,21 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	beentry->st_session.total_running_time += st_session_diff.total_running_time;
+	beentry->st_session.total_running_count += st_session_diff.total_running_count;
+
+	beentry->st_session.total_idle_time += st_session_diff.total_idle_time;
+	beentry->st_session.total_idle_count += st_session_diff.total_idle_count;
+
+	beentry->st_session.total_transaction_idle_time += st_session_diff.total_transaction_idle_time;
+	beentry->st_session.total_transaction_idle_count += st_session_diff.total_transaction_idle_count;
+
+	beentry->st_session.total_transaction_idle_aborted_time += st_session_diff.total_transaction_idle_aborted_time;
+	beentry->st_session.total_transaction_idle_aborted_count += st_session_diff.total_transaction_idle_aborted_count;
+
+	beentry->st_session.total_fastpath_time += st_session_diff.total_fastpath_time;
+	beentry->st_session.total_fastpath_count += st_session_diff.total_fastpath_count;
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 6737493402..3a76a5bf06 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -297,6 +297,76 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }
 
+/*
+ * Returns accumulated statistics of current PG backends.
+ */
+Datum
+pg_stat_get_session(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_GET_SESSION_COLS	11
+	int			num_backends = pgstat_fetch_stat_numbackends();
+	int			curr_backend;
+	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	InitMaterializedSRF(fcinfo, 0);
+
+	/* 1-based index */
+	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
+	{
+		/* for each row */
+		Datum		values[PG_STAT_GET_SESSION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SESSION_COLS] = {0};
+		LocalPgBackendStatus *local_beentry;
+		PgBackendStatus *beentry;
+
+		/* Get the next one in the list */
+		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
+		beentry = &local_beentry->backendStatus;
+
+		/* If looking for specific PID, ignore all the others */
+		if (pid != -1 && beentry->st_procpid != pid)
+			continue;
+
+		/* Values available to all callers */
+		values[0] = Int32GetDatum(beentry->st_procpid);
+
+		/* Values only available to role member or pg_read_all_stats */
+		if (HAS_PGSTAT_PERMISSIONS(beentry->st_userid)){
+			/* convert to msec */
+			values[1] = Float8GetDatum(beentry->st_session.total_running_time / 1000.0);
+			values[2] = Int64GetDatum(beentry->st_session.total_running_count);
+			values[3] = Float8GetDatum(beentry->st_session.total_idle_time / 1000.0);
+			values[4] = Int64GetDatum(beentry->st_session.total_idle_count);
+			values[5] = Float8GetDatum(beentry->st_session.total_transaction_idle_time / 1000.0);
+			values[6] = Int64GetDatum(beentry->st_session.total_transaction_idle_count);
+			values[7] = Float8GetDatum(beentry->st_session.total_transaction_idle_aborted_time / 1000.0);
+			values[8] = Int64GetDatum(beentry->st_session.total_transaction_idle_aborted_count);
+			values[9] = Float8GetDatum(beentry->st_session.total_fastpath_time / 1000.0);
+			values[10] = Int64GetDatum(beentry->st_session.total_fastpath_count);
+		} else {
+			nulls[1] = true;
+			nulls[2] = true;
+			nulls[3] = true;
+			nulls[4] = true;
+			nulls[5] = true;
+			nulls[6] = true;
+			nulls[7] = true;
+			nulls[8] = true;
+			nulls[9] = true;
+			nulls[10] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+
+		/* If only a single backend was requested, and we found it, break. */
+		if (pid != -1)
+			break;
+	}
+
+	return (Datum) 0;
+}
+
 /*
  * Returns activity of PG backends.
  */
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index c0f2a8a77c..4c063e2422 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5408,6 +5408,15 @@
   proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
   proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
   prosrc => 'pg_stat_get_activity' },
+{ oid => '2173',
+  descr => 'statistics: cumulative information about currently active backends',
+  proname => 'pg_stat_get_session', prorows => '100', proisstrict => 'f',
+  proretset => 't', provolatile => 's', proparallel => 'r',
+  prorettype => 'record', proargtypes => 'int4',
+  proallargtypes => '{int4,int4,float8,int8,float8,int8,float8,int8,float8,int8,float8,int8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,pid,total_running_time,total_running_count,total_idle_time,total_idle_count,total_transaction_idle_time,total_transaction_idle_count,total_transaction_idle_aborted_time,total_transaction_idle_aborted_count,total_fastpath_time,total_fastpath_count}',
+  prosrc => 'pg_stat_get_session' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
   proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index f7bd83113a..17eeb02a84 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -80,6 +80,26 @@ typedef struct PgBackendGSSStatus
 
 } PgBackendGSSStatus;
 
+/*
+ * PgBackendSessionStatus
+ *
+ * For each session, we keep counters accumulated since the start of the session
+ * in a separate struct. The struct is always filled.
+ *
+ */
+typedef struct PgBackendSessionStatus
+{
+	int64		total_running_time;
+	int64		total_running_count;
+	int64		total_idle_time;
+	int64		total_idle_count;
+	int64		total_transaction_idle_time;
+	int64		total_transaction_idle_count;
+	int64		total_transaction_idle_aborted_time;
+	int64		total_transaction_idle_aborted_count;
+	int64		total_fastpath_time;
+	int64		total_fastpath_count;
+} PgBackendSessionStatus;
 
 /* ----------
  * PgBackendStatus
@@ -169,6 +189,9 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* Counters accumulated since the start of the session */
+	PgBackendSessionStatus st_session;
 } PgBackendStatus;
 
 
@@ -233,6 +256,20 @@ typedef struct PgBackendStatus
 	 ((before_changecount) & 1) == 0)
 
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_RUNNING(s) \
+	((s)->st_state == STATE_RUNNING)
+#define PGSTAT_IS_FASTPATH(s) \
+	((s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLE(s) \
+	((s)->st_state == STATE_IDLE)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION)
+#define PGSTAT_IS_IDLEINTRANSACTION_ABORTED(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+
 /* ----------
  * LocalPgBackendStatus
  *
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index e7a2f5856a..73f10c8477 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2071,6 +2071,18 @@ pg_stat_replication_slots| SELECT s.slot_name,
    FROM pg_replication_slots r,
     LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset)
   WHERE (r.datoid IS NOT NULL);
+pg_stat_session| SELECT pid,
+    total_running_time,
+    total_running_count,
+    total_idle_time,
+    total_idle_count,
+    total_transaction_idle_time,
+    total_transaction_idle_count,
+    total_transaction_idle_aborted_time,
+    total_transaction_idle_aborted_count,
+    total_fastpath_time,
+    total_fastpath_count
+   FROM pg_stat_get_session(NULL::integer) s(pid, total_running_time, total_running_count, total_idle_time, total_idle_count, total_transaction_idle_time, total_transaction_idle_count, total_transaction_idle_aborted_time, total_transaction_idle_aborted_count, total_fastpath_time, total_fastpath_count);
 pg_stat_slru| SELECT name,
     blks_zeroed,
     blks_hit,
-- 
2.34.1

From 329db9a594b96499135bcbfdfad674f6af7ae1dc Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Tue, 22 Nov 2022 09:23:32 +0100
Subject: [PATCH] Add pg_stat_session

Author: Sergey Dudoladov

Adds pg_stat_session view to track statistics accumulated during
 lifetime of a session (client backend).

catversion bump is necessary due to a new view / function

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, and Atsushi
Torikoshi

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 134 ++++++++++++++++++++
 src/backend/catalog/system_views.sql        |  13 ++
 src/backend/utils/activity/backend_status.c |  57 +++++++--
 src/backend/utils/adt/pgstatfuncs.c         |  70 ++++++++++
 src/include/catalog/pg_proc.dat             |   9 ++
 src/include/utils/backend_status.h          |  32 +++++
 src/test/regress/expected/rules.out         |  10 ++
 src/test/regress/expected/sysviews.out      |   7 +
 src/test/regress/sql/sysviews.sql           |   3 +
 9 files changed, 325 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 5cfdc70c03..aa759e36c5 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -414,6 +414,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        See <xref linkend="copy-progress-reporting"/>.
       </entry>
      </row>
+
+     <row>
+      <entry>
+       <structname>pg_stat_session</structname>
+       <indexterm><primary>pg_stat_session</primary></indexterm>
+      </entry>
+      <entry>
+       One row per client backend, showing information related to
+       the currently accumulated activity of that process, such as time spent in
+       a certain state.
+       See <link linkend="monitoring-pg-stat-session-view">
+       <structname>pg_stat_session</structname></link> for details.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
@@ -5755,6 +5769,110 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
    </tgroup>
   </table>
 
+  <table id="monitoring-pg-stat-session-view" xreflabel="pg_stat_session">
+   <title><structname>pg_stat_session</structname> View</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>pid</structfield> <type>integer</type>
+      </para>
+      <para>
+       Process ID of this client backend.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_running_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+    <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_running_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_aborted_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction (aborted)</literal> 
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>total_transaction_idle_aborted_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+    </tbody>
+   </tgroup>
+  </table>
+
  </sect2>
 
  <sect2 id="monitoring-stats-functions">
@@ -5822,6 +5940,22 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_get_session</primary>
+        </indexterm>
+        <function>pg_stat_get_session</function> ( <type>integer</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Returns a record of information about the client backend with the specified
+        process ID, or one record for each active backend in the system
+        if <literal>NULL</literal> is specified.  The fields returned are a
+        subset of those in the <structname>pg_stat_session</structname> view.
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index c18fea8362..8f073b442c 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -872,6 +872,19 @@ CREATE VIEW pg_stat_activity AS
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
 
+CREATE VIEW pg_stat_session AS
+    SELECT
+            s.pid,
+            s.total_running_time,
+            s.total_running_count,
+            s.total_idle_time,
+            s.total_idle_count,
+            s.total_transaction_idle_time,
+            s.total_transaction_idle_count,
+            s.total_transaction_idle_aborted_time,
+            s.total_transaction_idle_aborted_count
+     FROM pg_stat_get_session(NULL) as s;
+
 CREATE VIEW pg_stat_replication AS
     SELECT
             S.pid,
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 38f91a495b..b20ef8c51e 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -338,6 +338,8 @@ pgstat_bestart(void)
 	lbeentry.st_xact_start_timestamp = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
+	MemSet(&lbeentry.st_session, 0, sizeof(lbeentry.st_session));
+
 	/* We have userid for client-backends, wal-sender and bgworker processes */
 	if (lbeentry.st_backendType == B_BACKEND
 		|| lbeentry.st_backendType == B_WAL_SENDER
@@ -526,6 +528,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz current_timestamp;
 	int			len = 0;
 
+	PgBackendSessionStatus st_session_diff;
+	MemSet(&st_session_diff, 0, sizeof(st_session_diff));
+
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
 	if (!beentry)
@@ -551,6 +556,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+			MemSet(&beentry->st_session, 0, sizeof(beentry->st_session));
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -573,27 +579,44 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	current_timestamp = GetCurrentTimestamp();
 
 	/*
-	 * If the state has changed from "active" or "idle in transaction",
-	 * calculate the duration.
+	 * If a client backend has changed state, update per-database and per-session counters.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
-		state != beentry->st_state)
+	if ((PGSTAT_IS_ACTIVE(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry) || 
+		 PGSTAT_IS_IDLE(beentry)) &&
+		state != beentry->st_state &&
+		beentry->st_backendType == B_BACKEND)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
+		usecs_diff = secs * 1000000 + usecs;
 
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
+		/* Keep statistics for pg_stat_database intact */
+		if (PGSTAT_IS_ACTIVE(beentry))
 			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
+		else if (PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+				 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry))
 			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+
+		if (PGSTAT_IS_ACTIVE(beentry)) {
+			st_session_diff.total_running_time = usecs_diff;
+			st_session_diff.total_running_count += 1;
+		} else if (PGSTAT_IS_IDLE(beentry)){
+			st_session_diff.total_idle_time = usecs_diff;
+			st_session_diff.total_idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION(beentry)){
+			st_session_diff.total_transaction_idle_time = usecs_diff;
+			st_session_diff.total_transaction_idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry)){
+			st_session_diff.total_transaction_idle_aborted_time = usecs_diff;
+			st_session_diff.total_transaction_idle_aborted_count += 1;
+		}
 	}
 
 	/*
@@ -619,6 +642,20 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	if (beentry->st_backendType == B_BACKEND) {
+		beentry->st_session.total_running_time += st_session_diff.total_running_time;
+		beentry->st_session.total_running_count += st_session_diff.total_running_count;
+
+		beentry->st_session.total_idle_time += st_session_diff.total_idle_time;
+		beentry->st_session.total_idle_count += st_session_diff.total_idle_count;
+
+		beentry->st_session.total_transaction_idle_time += st_session_diff.total_transaction_idle_time;
+		beentry->st_session.total_transaction_idle_count += st_session_diff.total_transaction_idle_count;
+
+		beentry->st_session.total_transaction_idle_aborted_time += st_session_diff.total_transaction_idle_aborted_time;
+		beentry->st_session.total_transaction_idle_aborted_count += st_session_diff.total_transaction_idle_aborted_count;
+	}
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 49adc319fc..6eb2384618 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -297,6 +297,76 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }
 
+/*
+ * Returns accumulated statistics of current PG backends.
+ */
+Datum
+pg_stat_get_session(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_GET_SESSION_COLS	9
+	int			num_backends = pgstat_fetch_stat_numbackends();
+	int			curr_backend;
+	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	InitMaterializedSRF(fcinfo, 0);
+
+	/* 1-based index */
+	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
+	{
+		/* for each row */
+		Datum		values[PG_STAT_GET_SESSION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SESSION_COLS] = {0};
+		LocalPgBackendStatus *local_beentry;
+		PgBackendStatus *beentry;
+
+		/* Get the next one in the list */
+		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
+		beentry = &local_beentry->backendStatus;
+
+		/* Report statistics only for client backends */
+		if (beentry->st_backendType != B_BACKEND)
+			continue;
+
+		/* If looking for specific PID, ignore all the others */
+		if (pid != -1 && beentry->st_procpid != pid)
+			continue;
+
+		/* Values available to all callers */
+		values[0] = Int32GetDatum(beentry->st_procpid);
+
+		/* Values only available to role member or pg_read_all_stats */
+		if (HAS_PGSTAT_PERMISSIONS(beentry->st_userid)){
+			/* convert to msec */
+			values[1] = Float8GetDatum(beentry->st_session.total_running_time / 1000.0);
+			values[2] = Int64GetDatum(beentry->st_session.total_running_count);
+			values[3] = Float8GetDatum(beentry->st_session.total_idle_time / 1000.0);
+			values[4] = Int64GetDatum(beentry->st_session.total_idle_count);
+			values[5] = Float8GetDatum(beentry->st_session.total_transaction_idle_time / 1000.0);
+			values[6] = Int64GetDatum(beentry->st_session.total_transaction_idle_count);
+			values[7] = Float8GetDatum(beentry->st_session.total_transaction_idle_aborted_time / 1000.0);
+			values[8] = Int64GetDatum(beentry->st_session.total_transaction_idle_aborted_count);
+		} else {
+			nulls[1] = true;
+			nulls[2] = true;
+			nulls[3] = true;
+			nulls[4] = true;
+			nulls[5] = true;
+			nulls[6] = true;
+			nulls[7] = true;
+			nulls[8] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+
+		/* If only a single backend was requested, and we found it, break. */
+		if (pid != -1)
+			break;
+	}
+
+	return (Datum) 0;
+}
+
 /*
  * Returns activity of PG backends.
  */
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 6996073989..60ac6ea3de 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5417,6 +5417,15 @@
   proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
   proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,gss_delegation,leader_pid,query_id}',
   prosrc => 'pg_stat_get_activity' },
+{ oid => '2173',
+  descr => 'statistics: cumulative information about currently active client backends',
+  proname => 'pg_stat_get_session', prorows => '100', proisstrict => 'f',
+  proretset => 't', provolatile => 's', proparallel => 'r',
+  prorettype => 'record', proargtypes => 'int4',
+  proallargtypes => '{int4,int4,float8,int8,float8,int8,float8,int8,float8,int8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,pid,total_running_time,total_running_count,total_idle_time,total_idle_count,total_transaction_idle_time,total_transaction_idle_count,total_transaction_idle_aborted_time,total_transaction_idle_aborted_count}',
+  prosrc => 'pg_stat_get_session' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
   proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 16500d53b2..b0099d307e 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -81,6 +81,24 @@ typedef struct PgBackendGSSStatus
 
 } PgBackendGSSStatus;
 
+/*
+ * PgBackendSessionStatus
+ *
+ * For each session, we keep counters accumulated since the start of the session
+ * in a separate struct. The struct is always filled.
+ *
+ */
+typedef struct PgBackendSessionStatus
+{
+	int64		total_running_time;
+	int64		total_running_count;
+	int64		total_idle_time;
+	int64		total_idle_count;
+	int64		total_transaction_idle_time;
+	int64		total_transaction_idle_count;
+	int64		total_transaction_idle_aborted_time;
+	int64		total_transaction_idle_aborted_count;
+} PgBackendSessionStatus;
 
 /* ----------
  * PgBackendStatus
@@ -170,6 +188,9 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* Counters accumulated since the start of the session */
+	PgBackendSessionStatus st_session;
 } PgBackendStatus;
 
 
@@ -234,6 +255,17 @@ typedef struct PgBackendStatus
 	 ((before_changecount) & 1) == 0)
 
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLE(s) \
+	((s)->st_state == STATE_IDLE)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION)
+#define PGSTAT_IS_IDLEINTRANSACTION_ABORTED(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+
+
 /* ----------
  * LocalPgBackendStatus
  *
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 7fd81e6a7d..9eb67d4763 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2094,6 +2094,16 @@ pg_stat_replication_slots| SELECT s.slot_name,
    FROM pg_replication_slots r,
     LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset)
   WHERE (r.datoid IS NOT NULL);
+pg_stat_session| SELECT pid,
+    total_running_time,
+    total_running_count,
+    total_idle_time,
+    total_idle_count,
+    total_transaction_idle_time,
+    total_transaction_idle_count,
+    total_transaction_idle_aborted_time,
+    total_transaction_idle_aborted_count
+   FROM pg_stat_get_session(NULL::integer) s(pid, total_running_time, total_running_count, total_idle_time, total_idle_count, total_transaction_idle_time, total_transaction_idle_count, total_transaction_idle_aborted_time, total_transaction_idle_aborted_count);
 pg_stat_slru| SELECT name,
     blks_zeroed,
     blks_hit,
diff --git a/src/test/regress/expected/sysviews.out b/src/test/regress/expected/sysviews.out
index 001c6e7eb9..e66c08cd40 100644
--- a/src/test/regress/expected/sysviews.out
+++ b/src/test/regress/expected/sysviews.out
@@ -167,3 +167,10 @@ select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
  t
 (1 row)
 
+select total_idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select total_idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
diff --git a/src/test/regress/sql/sysviews.sql b/src/test/regress/sql/sysviews.sql
index 351e469c77..6545e65d21 100644
--- a/src/test/regress/sql/sysviews.sql
+++ b/src/test/regress/sql/sysviews.sql
@@ -68,3 +68,6 @@ set timezone_abbreviations = 'Australia';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
 set timezone_abbreviations = 'India';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
+
+select total_idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select total_idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
\ No newline at end of file
-- 
2.34.1

From 05f5117be52b613bb9d11114833eec38e152c6f9 Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Thu, 1 Feb 2024 16:11:36 +0100
Subject: [PATCH] Add pg_stat_session

Author: Sergey Dudoladov

Adds pg_stat_session view to track statistics accumulated during
 lifetime of a session (client backend).

catversion bump is necessary due to a new view / function

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, Atsushi
Torikoshi, and Andrei Zubkov

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 134 ++++++++++++++++++++
 src/backend/catalog/system_views.sql        |  13 ++
 src/backend/utils/activity/backend_status.c |  64 ++++++++--
 src/backend/utils/adt/pgstatfuncs.c         |  70 ++++++++++
 src/include/catalog/pg_proc.dat             |   9 ++
 src/include/utils/backend_status.h          |  32 +++++
 src/test/regress/expected/rules.out         |  10 ++
 src/test/regress/expected/sysviews.out      |   7 +
 src/test/regress/sql/sysviews.sql           |   3 +
 9 files changed, 329 insertions(+), 13 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index d9b8b37585..b10423428a 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -414,6 +414,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        See <xref linkend="copy-progress-reporting"/>.
       </entry>
      </row>
+
+     <row>
+      <entry>
+       <structname>pg_stat_session</structname>
+       <indexterm><primary>pg_stat_session</primary></indexterm>
+      </entry>
+      <entry>
+       One row per client backend, showing information related to
+       the currently accumulated activity of that process, such as time spent in
+       a certain state.
+       See <link linkend="monitoring-pg-stat-session-view">
+       <structname>pg_stat_session</structname></link> for details.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
@@ -4589,6 +4603,110 @@ description | Waiting for a newly initialized WAL file to reach durable storage
    </tgroup>
   </table>

+  <table id="monitoring-pg-stat-session-view" xreflabel="pg_stat_session">
+   <title><structname>pg_stat_session</structname> View</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>pid</structfield> <type>integer</type>
+      </para>
+      <para>
+       Process ID of this client backend.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+    <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+    </tbody>
+   </tgroup>
+  </table>
+
  </sect2>

  <sect2 id="monitoring-stats-functions">
@@ -5128,6 +5246,22 @@ FROM pg_stat_get_backend_idset() AS backendid;
        </para></entry>
       </row>

+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_get_session</primary>
+        </indexterm>
+        <function>pg_stat_get_session</function> ( <type>integer</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Returns a record of information about the client backend with the specified
+        process ID, or one record for each active backend in the system
+        if <literal>NULL</literal> is specified.  The fields returned are a
+        subset of those in the <structname>pg_stat_session</structname> view.
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 6791bff9dd..79db3af28b 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -893,6 +893,19 @@ CREATE VIEW pg_stat_activity AS
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);

+CREATE VIEW pg_stat_session AS
+    SELECT
+            s.pid,
+            s.active_time,
+            s.active_count,
+            s.idle_time,
+            s.idle_count,
+            s.idle_in_transaction_time,
+            s.idle_in_transaction_count,
+            s.idle_in_transaction_aborted_time,
+            s.idle_in_transaction_aborted_count
+     FROM pg_stat_get_session(NULL) as s;
+
 CREATE VIEW pg_stat_replication AS
     SELECT
             S.pid,
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 1a1050c8da..31763a1efd 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -338,6 +338,8 @@ pgstat_bestart(void)
 	lbeentry.st_xact_start_timestamp = 0;
 	lbeentry.st_databaseid = MyDatabaseId;

+	MemSet(&lbeentry.st_session, 0, sizeof(lbeentry.st_session));
+
 	/* We have userid for client-backends, wal-sender and bgworker processes */
 	if (lbeentry.st_backendType == B_BACKEND
 		|| lbeentry.st_backendType == B_WAL_SENDER
@@ -526,6 +528,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz current_timestamp;
 	int			len = 0;

+	PgBackendSessionStatus st_session_diff;
+	MemSet(&st_session_diff, 0, sizeof(st_session_diff));
+
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);

 	if (!beentry)
@@ -551,6 +556,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+			MemSet(&beentry->st_session, 0, sizeof(beentry->st_session));
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -573,27 +579,45 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	current_timestamp = GetCurrentTimestamp();

 	/*
-	 * If the state has changed from "active" or "idle in transaction",
-	 * calculate the duration.
+	 * If a client backend has changed state, update per-database and per-session counters.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
-		state != beentry->st_state)
+	if ((PGSTAT_IS_ACTIVE(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry) ||
+		 PGSTAT_IS_IDLE(beentry)) &&
+		state != beentry->st_state &&
+		beentry->st_backendType == B_BACKEND)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;

 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
-
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+		usecs_diff = secs * 1000000 + usecs;
+
+		/* compute values for pg_stat_database */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
+		else if (PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+				 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry))
+			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
+
+		/* compute values for pg_stat_session */
+		if (PGSTAT_IS_ACTIVE(beentry)) {
+			st_session_diff.active_time = usecs_diff;
+			st_session_diff.active_count += 1;
+		} else if (PGSTAT_IS_IDLE(beentry)){
+			st_session_diff.idle_time = usecs_diff;
+			st_session_diff.idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION(beentry)){
+			st_session_diff.idle_in_transaction_time = usecs_diff;
+			st_session_diff.idle_in_transaction_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry)){
+			st_session_diff.idle_in_transaction_aborted_time = usecs_diff;
+			st_session_diff.idle_in_transaction_aborted_count += 1;
+		}
 	}

 	/*
@@ -619,6 +643,20 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}

+	if (beentry->st_backendType == B_BACKEND) {
+		beentry->st_session.active_time += st_session_diff.active_time;
+		beentry->st_session.active_count += st_session_diff.active_count;
+
+		beentry->st_session.idle_time += st_session_diff.idle_time;
+		beentry->st_session.idle_count += st_session_diff.idle_count;
+
+		beentry->st_session.idle_in_transaction_time += st_session_diff.idle_in_transaction_time;
+		beentry->st_session.idle_in_transaction_count += st_session_diff.idle_in_transaction_count;
+
+		beentry->st_session.idle_in_transaction_aborted_time += st_session_diff.idle_in_transaction_aborted_time;
+		beentry->st_session.idle_in_transaction_aborted_count += st_session_diff.idle_in_transaction_aborted_count;
+	}
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }

diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 30a2063505..a4a8c7204c 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -298,6 +298,76 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }

+/*
+ * Returns accumulated statistics of current PG backends.
+ */
+Datum
+pg_stat_get_session(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_GET_SESSION_COLS	9
+	int			num_backends = pgstat_fetch_stat_numbackends();
+	int			curr_backend;
+	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	InitMaterializedSRF(fcinfo, 0);
+
+	/* 1-based index */
+	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
+	{
+		/* for each row */
+		Datum		values[PG_STAT_GET_SESSION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SESSION_COLS] = {0};
+		LocalPgBackendStatus *local_beentry;
+		PgBackendStatus *beentry;
+
+		/* Get the next one in the list */
+		local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
+		beentry = &local_beentry->backendStatus;
+
+		/* Report statistics only for client backends */
+		if (beentry->st_backendType != B_BACKEND)
+			continue;
+
+		/* If looking for specific PID, ignore all the others */
+		if (pid != -1 && beentry->st_procpid != pid)
+			continue;
+
+		/* Values available to all callers */
+		values[0] = Int32GetDatum(beentry->st_procpid);
+
+		/* Values only available to role member or pg_read_all_stats */
+		if (HAS_PGSTAT_PERMISSIONS(beentry->st_userid)){
+			/* convert to msec */
+			values[1] = Float8GetDatum(beentry->st_session.active_time / 1000.0);
+			values[2] = Int64GetDatum(beentry->st_session.active_count);
+			values[3] = Float8GetDatum(beentry->st_session.idle_time / 1000.0);
+			values[4] = Int64GetDatum(beentry->st_session.idle_count);
+			values[5] = Float8GetDatum(beentry->st_session.idle_in_transaction_time / 1000.0);
+			values[6] = Int64GetDatum(beentry->st_session.idle_in_transaction_count);
+			values[7] = Float8GetDatum(beentry->st_session.idle_in_transaction_aborted_time / 1000.0);
+			values[8] = Int64GetDatum(beentry->st_session.idle_in_transaction_aborted_count);
+		} else {
+			nulls[1] = true;
+			nulls[2] = true;
+			nulls[3] = true;
+			nulls[4] = true;
+			nulls[5] = true;
+			nulls[6] = true;
+			nulls[7] = true;
+			nulls[8] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+
+		/* If only a single backend was requested, and we found it, break. */
+		if (pid != -1)
+			break;
+	}
+
+	return (Datum) 0;
+}
+
 /*
  * Returns activity of PG backends.
  */
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 29af4ce65d..1c81f70f9b 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5450,6 +5450,15 @@
   proargtypes => '', proallargtypes => '{text,text,text}',
   proargmodes => '{o,o,o}', proargnames => '{type,name,description}',
   prosrc => 'pg_get_wait_events' },
+{ oid => '2173',
+  descr => 'statistics: cumulative information about currently active client backends',
+  proname => 'pg_stat_get_session', prorows => '100', proisstrict => 'f',
+  proretset => 't', provolatile => 's', proparallel => 'r',
+  prorettype => 'record', proargtypes => 'int4',
+  proallargtypes => '{int4,int4,float8,int8,float8,int8,float8,int8,float8,int8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,pid,active_time,active_count,idle_time,idle_count,idle_in_transaction_time,idle_in_transaction_count,idle_in_transaction_aborted_time,idle_in_transaction_aborted_count}',
+  prosrc => 'pg_stat_get_session' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
   proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 7b8a34f64f..830df6b9fa 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -81,6 +81,24 @@ typedef struct PgBackendGSSStatus

 } PgBackendGSSStatus;

+/*
+ * PgBackendSessionStatus
+ *
+ * For each session, we keep counters accumulated since the start of the session
+ * in a separate struct. The struct is always filled.
+ *
+ */
+typedef struct PgBackendSessionStatus
+{
+	int64		active_time;
+	int64		active_count;
+	int64		idle_time;
+	int64		idle_count;
+	int64		idle_in_transaction_time;
+	int64		idle_in_transaction_count;
+	int64		idle_in_transaction_aborted_time;
+	int64		idle_in_transaction_aborted_count;
+} PgBackendSessionStatus;

 /* ----------
  * PgBackendStatus
@@ -170,6 +188,9 @@ typedef struct PgBackendStatus

 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* Counters accumulated since the start of the session */
+	PgBackendSessionStatus st_session;
 } PgBackendStatus;


@@ -234,6 +255,17 @@ typedef struct PgBackendStatus
 	 ((before_changecount) & 1) == 0)


+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLE(s) \
+	((s)->st_state == STATE_IDLE)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION)
+#define PGSTAT_IS_IDLEINTRANSACTION_ABORTED(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+
+
 /* ----------
  * LocalPgBackendStatus
  *
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index abc944e8b8..108b5efd15 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2100,6 +2100,16 @@ pg_stat_replication_slots| SELECT s.slot_name,
    FROM pg_replication_slots r,
     LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset)
   WHERE (r.datoid IS NOT NULL);
+pg_stat_session| SELECT pid,
+    active_time,
+    active_count,
+    idle_time,
+    idle_count,
+    idle_in_transaction_time,
+    idle_in_transaction_count,
+    idle_in_transaction_aborted_time,
+    idle_in_transaction_aborted_count
+   FROM pg_stat_get_session(NULL::integer) s(pid, active_time, active_count, idle_time, idle_count, idle_in_transaction_time, idle_in_transaction_count, idle_in_transaction_aborted_time, idle_in_transaction_aborted_count);
 pg_stat_slru| SELECT name,
     blks_zeroed,
     blks_hit,
diff --git a/src/test/regress/expected/sysviews.out b/src/test/regress/expected/sysviews.out
index 9be7aca2b8..d3fe88b6a5 100644
--- a/src/test/regress/expected/sysviews.out
+++ b/src/test/regress/expected/sysviews.out
@@ -185,3 +185,10 @@ select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
  t
 (1 row)

+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+ ok
+----
+ t
+(1 row)
+
diff --git a/src/test/regress/sql/sysviews.sql b/src/test/regress/sql/sysviews.sql
index 6b4e24601d..910d6a6851 100644
--- a/src/test/regress/sql/sysviews.sql
+++ b/src/test/regress/sql/sysviews.sql
@@ -72,3 +72,6 @@ set timezone_abbreviations = 'Australia';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
 set timezone_abbreviations = 'India';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
\ No newline at end of file
--
2.34.1

From 66ac1efe5424aa1385744a60047ffd44d42dd244 Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Thu, 1 Feb 2024 16:11:36 +0100
Subject: [PATCH] Add pg_stat_session

Author: Sergey Dudoladov

Adds pg_stat_session view to track statistics accumulated during
 lifetime of a session (client backend).

catversion bump is necessary due to a new view / function

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, Atsushi
Torikoshi, and Andrei Zubkov

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 134 ++++++++++++++++++++
 src/backend/catalog/system_views.sql        |  13 ++
 src/backend/utils/activity/backend_status.c |  64 ++++++++--
 src/backend/utils/adt/pgstatfuncs.c         |  70 ++++++++++
 src/include/catalog/pg_proc.dat             |   9 ++
 src/include/utils/backend_status.h          |  32 +++++
 src/test/regress/expected/rules.out         |  10 ++
 src/test/regress/expected/sysviews.out      |  37 ++++++
 src/test/regress/sql/sysviews.sql           |  17 +++
 9 files changed, 373 insertions(+), 13 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index d9b8b37585..b10423428a 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -414,6 +414,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        See <xref linkend="copy-progress-reporting"/>.
       </entry>
      </row>
+
+     <row>
+      <entry>
+       <structname>pg_stat_session</structname>
+       <indexterm><primary>pg_stat_session</primary></indexterm>
+      </entry>
+      <entry>
+       One row per client backend, showing information related to
+       the currently accumulated activity of that process, such as time spent in
+       a certain state.
+       See <link linkend="monitoring-pg-stat-session-view">
+       <structname>pg_stat_session</structname></link> for details.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
@@ -4589,6 +4603,110 @@ description | Waiting for a newly initialized WAL file to reach durable storage
    </tgroup>
   </table>
 
+  <table id="monitoring-pg-stat-session-view" xreflabel="pg_stat_session">
+   <title><structname>pg_stat_session</structname> View</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>pid</structfield> <type>integer</type>
+      </para>
+      <para>
+       Process ID of this client backend.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+    <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+    </tbody>
+   </tgroup>
+  </table>
+
  </sect2>
 
  <sect2 id="monitoring-stats-functions">
@@ -5128,6 +5246,22 @@ FROM pg_stat_get_backend_idset() AS backendid;
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_get_session</primary>
+        </indexterm>
+        <function>pg_stat_get_session</function> ( <type>integer</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Returns a record of information about the client backend with the specified
+        process ID, or one record for each active backend in the system
+        if <literal>NULL</literal> is specified.  The fields returned are a
+        subset of those in the <structname>pg_stat_session</structname> view.
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 6791bff9dd..79db3af28b 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -893,6 +893,19 @@ CREATE VIEW pg_stat_activity AS
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
 
+CREATE VIEW pg_stat_session AS
+    SELECT
+            s.pid,
+            s.active_time,
+            s.active_count,
+            s.idle_time,
+            s.idle_count,
+            s.idle_in_transaction_time,
+            s.idle_in_transaction_count,
+            s.idle_in_transaction_aborted_time,
+            s.idle_in_transaction_aborted_count
+     FROM pg_stat_get_session(NULL) as s;
+
 CREATE VIEW pg_stat_replication AS
     SELECT
             S.pid,
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 1a1050c8da..31763a1efd 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -338,6 +338,8 @@ pgstat_bestart(void)
 	lbeentry.st_xact_start_timestamp = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
+	MemSet(&lbeentry.st_session, 0, sizeof(lbeentry.st_session));
+
 	/* We have userid for client-backends, wal-sender and bgworker processes */
 	if (lbeentry.st_backendType == B_BACKEND
 		|| lbeentry.st_backendType == B_WAL_SENDER
@@ -526,6 +528,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz current_timestamp;
 	int			len = 0;
 
+	PgBackendSessionStatus st_session_diff;
+	MemSet(&st_session_diff, 0, sizeof(st_session_diff));
+
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
 	if (!beentry)
@@ -551,6 +556,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+			MemSet(&beentry->st_session, 0, sizeof(beentry->st_session));
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -573,27 +579,45 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	current_timestamp = GetCurrentTimestamp();
 
 	/*
-	 * If the state has changed from "active" or "idle in transaction",
-	 * calculate the duration.
+	 * If a client backend has changed state, update per-database and per-session counters.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
-		state != beentry->st_state)
+	if ((PGSTAT_IS_ACTIVE(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry) ||
+		 PGSTAT_IS_IDLE(beentry)) &&
+		state != beentry->st_state &&
+		beentry->st_backendType == B_BACKEND)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
-
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+		usecs_diff = secs * 1000000 + usecs;
+
+		/* compute values for pg_stat_database */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
+		else if (PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+				 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry))
+			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
+
+		/* compute values for pg_stat_session */
+		if (PGSTAT_IS_ACTIVE(beentry)) {
+			st_session_diff.active_time = usecs_diff;
+			st_session_diff.active_count += 1;
+		} else if (PGSTAT_IS_IDLE(beentry)){
+			st_session_diff.idle_time = usecs_diff;
+			st_session_diff.idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION(beentry)){
+			st_session_diff.idle_in_transaction_time = usecs_diff;
+			st_session_diff.idle_in_transaction_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry)){
+			st_session_diff.idle_in_transaction_aborted_time = usecs_diff;
+			st_session_diff.idle_in_transaction_aborted_count += 1;
+		}
 	}
 
 	/*
@@ -619,6 +643,20 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	if (beentry->st_backendType == B_BACKEND) {
+		beentry->st_session.active_time += st_session_diff.active_time;
+		beentry->st_session.active_count += st_session_diff.active_count;
+
+		beentry->st_session.idle_time += st_session_diff.idle_time;
+		beentry->st_session.idle_count += st_session_diff.idle_count;
+
+		beentry->st_session.idle_in_transaction_time += st_session_diff.idle_in_transaction_time;
+		beentry->st_session.idle_in_transaction_count += st_session_diff.idle_in_transaction_count;
+
+		beentry->st_session.idle_in_transaction_aborted_time += st_session_diff.idle_in_transaction_aborted_time;
+		beentry->st_session.idle_in_transaction_aborted_count += st_session_diff.idle_in_transaction_aborted_count;
+	}
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 30a2063505..a4a8c7204c 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -298,6 +298,76 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }
 
+/*
+ * Returns accumulated statistics of current PG backends.
+ */
+Datum
+pg_stat_get_session(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_GET_SESSION_COLS	9
+	int			num_backends = pgstat_fetch_stat_numbackends();
+	int			curr_backend;
+	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	InitMaterializedSRF(fcinfo, 0);
+
+	/* 1-based index */
+	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
+	{
+		/* for each row */
+		Datum		values[PG_STAT_GET_SESSION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SESSION_COLS] = {0};
+		LocalPgBackendStatus *local_beentry;
+		PgBackendStatus *beentry;
+
+		/* Get the next one in the list */
+		local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
+		beentry = &local_beentry->backendStatus;
+
+		/* Report statistics only for client backends */
+		if (beentry->st_backendType != B_BACKEND)
+			continue;
+
+		/* If looking for specific PID, ignore all the others */
+		if (pid != -1 && beentry->st_procpid != pid)
+			continue;
+
+		/* Values available to all callers */
+		values[0] = Int32GetDatum(beentry->st_procpid);
+
+		/* Values only available to role member or pg_read_all_stats */
+		if (HAS_PGSTAT_PERMISSIONS(beentry->st_userid)){
+			/* convert to msec */
+			values[1] = Float8GetDatum(beentry->st_session.active_time / 1000.0);
+			values[2] = Int64GetDatum(beentry->st_session.active_count);
+			values[3] = Float8GetDatum(beentry->st_session.idle_time / 1000.0);
+			values[4] = Int64GetDatum(beentry->st_session.idle_count);
+			values[5] = Float8GetDatum(beentry->st_session.idle_in_transaction_time / 1000.0);
+			values[6] = Int64GetDatum(beentry->st_session.idle_in_transaction_count);
+			values[7] = Float8GetDatum(beentry->st_session.idle_in_transaction_aborted_time / 1000.0);
+			values[8] = Int64GetDatum(beentry->st_session.idle_in_transaction_aborted_count);
+		} else {
+			nulls[1] = true;
+			nulls[2] = true;
+			nulls[3] = true;
+			nulls[4] = true;
+			nulls[5] = true;
+			nulls[6] = true;
+			nulls[7] = true;
+			nulls[8] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+
+		/* If only a single backend was requested, and we found it, break. */
+		if (pid != -1)
+			break;
+	}
+
+	return (Datum) 0;
+}
+
 /*
  * Returns activity of PG backends.
  */
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 29af4ce65d..1c81f70f9b 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5450,6 +5450,15 @@
   proargtypes => '', proallargtypes => '{text,text,text}',
   proargmodes => '{o,o,o}', proargnames => '{type,name,description}',
   prosrc => 'pg_get_wait_events' },
+{ oid => '2173',
+  descr => 'statistics: cumulative information about currently active client backends',
+  proname => 'pg_stat_get_session', prorows => '100', proisstrict => 'f',
+  proretset => 't', provolatile => 's', proparallel => 'r',
+  prorettype => 'record', proargtypes => 'int4',
+  proallargtypes => '{int4,int4,float8,int8,float8,int8,float8,int8,float8,int8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,pid,active_time,active_count,idle_time,idle_count,idle_in_transaction_time,idle_in_transaction_count,idle_in_transaction_aborted_time,idle_in_transaction_aborted_count}',
+  prosrc => 'pg_stat_get_session' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
   proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 7b8a34f64f..830df6b9fa 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -81,6 +81,24 @@ typedef struct PgBackendGSSStatus
 
 } PgBackendGSSStatus;
 
+/*
+ * PgBackendSessionStatus
+ *
+ * For each session, we keep counters accumulated since the start of the session
+ * in a separate struct. The struct is always filled.
+ *
+ */
+typedef struct PgBackendSessionStatus
+{
+	int64		active_time;
+	int64		active_count;
+	int64		idle_time;
+	int64		idle_count;
+	int64		idle_in_transaction_time;
+	int64		idle_in_transaction_count;
+	int64		idle_in_transaction_aborted_time;
+	int64		idle_in_transaction_aborted_count;
+} PgBackendSessionStatus;
 
 /* ----------
  * PgBackendStatus
@@ -170,6 +188,9 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* Counters accumulated since the start of the session */
+	PgBackendSessionStatus st_session;
 } PgBackendStatus;
 
 
@@ -234,6 +255,17 @@ typedef struct PgBackendStatus
 	 ((before_changecount) & 1) == 0)
 
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLE(s) \
+	((s)->st_state == STATE_IDLE)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION)
+#define PGSTAT_IS_IDLEINTRANSACTION_ABORTED(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+
+
 /* ----------
  * LocalPgBackendStatus
  *
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index abc944e8b8..108b5efd15 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2100,6 +2100,16 @@ pg_stat_replication_slots| SELECT s.slot_name,
    FROM pg_replication_slots r,
     LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset)
   WHERE (r.datoid IS NOT NULL);
+pg_stat_session| SELECT pid,
+    active_time,
+    active_count,
+    idle_time,
+    idle_count,
+    idle_in_transaction_time,
+    idle_in_transaction_count,
+    idle_in_transaction_aborted_time,
+    idle_in_transaction_aborted_count
+   FROM pg_stat_get_session(NULL::integer) s(pid, active_time, active_count, idle_time, idle_count, idle_in_transaction_time, idle_in_transaction_count, idle_in_transaction_aborted_time, idle_in_transaction_aborted_count);
 pg_stat_slru| SELECT name,
     blks_zeroed,
     blks_hit,
diff --git a/src/test/regress/expected/sysviews.out b/src/test/regress/expected/sysviews.out
index 9be7aca2b8..42b04d198b 100644
--- a/src/test/regress/expected/sysviews.out
+++ b/src/test/regress/expected/sysviews.out
@@ -185,3 +185,40 @@ select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
  t
 (1 row)
 
+select active_count as prev_active_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select active_count from pg_stat_session where pid = pg_backend_pid()) - :prev_active_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_in_transaction_count as prev_idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+commit;
+select (select idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_in_transaction_aborted_count as prev_idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+select non_existent_function();
+ERROR:  function non_existent_function() does not exist
+LINE 1: select non_existent_function();
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+rollback;
+select (select idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_aborted_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
diff --git a/src/test/regress/sql/sysviews.sql b/src/test/regress/sql/sysviews.sql
index 6b4e24601d..593a3176ca 100644
--- a/src/test/regress/sql/sysviews.sql
+++ b/src/test/regress/sql/sysviews.sql
@@ -72,3 +72,20 @@ set timezone_abbreviations = 'Australia';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
 set timezone_abbreviations = 'India';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
+
+select active_count as prev_active_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select active_count from pg_stat_session where pid = pg_backend_pid()) - :prev_active_count = 1 as ok;
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+
+select idle_in_transaction_count as prev_idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+commit;
+select (select idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_count = 1 as ok;
+
+select idle_in_transaction_aborted_count as prev_idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+select non_existent_function();
+rollback;
+select (select idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_aborted_count = 1 as ok;
\ No newline at end of file
-- 
2.34.1

From 54e4d85a6382fbb4baf4575c99310a6a61a738ac Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Thu, 1 Feb 2024 16:11:36 +0100
Subject: [PATCH] Add pg_stat_session

Author: Sergey Dudoladov

Adds pg_stat_session view to track statistics accumulated during
 lifetime of a session (client backend).

catversion bump is necessary due to a new view / function

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, Atsushi
Torikoshi, and Andrei Zubkov

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 134 ++++++++++++++++++++
 src/backend/catalog/system_views.sql        |  13 ++
 src/backend/utils/activity/backend_status.c |  64 ++++++++--
 src/backend/utils/adt/pgstatfuncs.c         |  70 ++++++++++
 src/include/catalog/pg_proc.dat             |   9 ++
 src/include/utils/backend_status.h          |  32 +++++
 src/test/regress/expected/rules.out         |  10 ++
 src/test/regress/expected/sysviews.out      |  39 ++++++
 src/test/regress/sql/sysviews.sql           |  21 +++
 9 files changed, 379 insertions(+), 13 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 840d7f8161..33c98425b4 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -414,6 +414,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        See <xref linkend="copy-progress-reporting"/>.
       </entry>
      </row>
+
+     <row>
+      <entry>
+       <structname>pg_stat_session</structname>
+       <indexterm><primary>pg_stat_session</primary></indexterm>
+      </entry>
+      <entry>
+       One row per client backend, showing information related to
+       the currently accumulated activity of that process, such as time spent in
+       a certain state.
+       See <link linkend="monitoring-pg-stat-session-view">
+       <structname>pg_stat_session</structname></link> for details.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
@@ -4739,6 +4753,110 @@ description | Waiting for a newly initialized WAL file to reach durable storage
    </tgroup>
   </table>
 
+  <table id="monitoring-pg-stat-session-view" xreflabel="pg_stat_session">
+   <title><structname>pg_stat_session</structname> View</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>pid</structfield> <type>integer</type>
+      </para>
+      <para>
+       Process ID of this client backend.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+    <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+    </tbody>
+   </tgroup>
+  </table>
+
  </sect2>
 
  <sect2 id="monitoring-stats-functions">
@@ -5278,6 +5396,22 @@ FROM pg_stat_get_backend_idset() AS backendid;
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_get_session</primary>
+        </indexterm>
+        <function>pg_stat_get_session</function> ( <type>integer</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Returns a row, showing statistics about the client backend with the
+        specified process ID, or one row per client backend
+        if <literal>NULL</literal> is specified. The fields returned are the
+        same as those of <structname>pg_stat_session</structname> view.
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index da9a8fe99f..93a78f7384 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -886,6 +886,19 @@ CREATE VIEW pg_stat_activity AS
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
 
+CREATE VIEW pg_stat_session AS
+    SELECT
+            s.pid,
+            s.active_time,
+            s.active_count,
+            s.idle_time,
+            s.idle_count,
+            s.idle_in_transaction_time,
+            s.idle_in_transaction_count,
+            s.idle_in_transaction_aborted_time,
+            s.idle_in_transaction_aborted_count
+     FROM pg_stat_get_session(NULL) as s;
+
 CREATE VIEW pg_stat_replication AS
     SELECT
             S.pid,
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index bdb3a296ca..1e3fc5ffec 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -317,6 +317,8 @@ pgstat_bestart(void)
 	lbeentry.st_xact_start_timestamp = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
+	MemSet(&lbeentry.st_session, 0, sizeof(lbeentry.st_session));
+
 	/* We have userid for client-backends, wal-sender and bgworker processes */
 	if (lbeentry.st_backendType == B_BACKEND
 		|| lbeentry.st_backendType == B_WAL_SENDER
@@ -505,6 +507,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz current_timestamp;
 	int			len = 0;
 
+	PgBackendSessionStatus st_session_diff;
+	MemSet(&st_session_diff, 0, sizeof(st_session_diff));
+
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
 	if (!beentry)
@@ -530,6 +535,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+			MemSet(&beentry->st_session, 0, sizeof(beentry->st_session));
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -552,27 +558,45 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	current_timestamp = GetCurrentTimestamp();
 
 	/*
-	 * If the state has changed from "active" or "idle in transaction",
-	 * calculate the duration.
+	 * If a client backend has changed state, update per-database and per-session counters.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
-		state != beentry->st_state)
+	if ((PGSTAT_IS_ACTIVE(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry) ||
+		 PGSTAT_IS_IDLE(beentry)) &&
+		state != beentry->st_state &&
+		beentry->st_backendType == B_BACKEND)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
-
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+		usecs_diff = secs * 1000000 + usecs;
+
+		/* compute values for pg_stat_database */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
+		else if (PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+				 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry))
+			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
+
+		/* compute values for pg_stat_session */
+		if (PGSTAT_IS_ACTIVE(beentry)) {
+			st_session_diff.active_time = usecs_diff;
+			st_session_diff.active_count += 1;
+		} else if (PGSTAT_IS_IDLE(beentry)){
+			st_session_diff.idle_time = usecs_diff;
+			st_session_diff.idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION(beentry)){
+			st_session_diff.idle_in_transaction_time = usecs_diff;
+			st_session_diff.idle_in_transaction_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry)){
+			st_session_diff.idle_in_transaction_aborted_time = usecs_diff;
+			st_session_diff.idle_in_transaction_aborted_count += 1;
+		}
 	}
 
 	/*
@@ -598,6 +622,20 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	if (beentry->st_backendType == B_BACKEND) {
+		beentry->st_session.active_time += st_session_diff.active_time;
+		beentry->st_session.active_count += st_session_diff.active_count;
+
+		beentry->st_session.idle_time += st_session_diff.idle_time;
+		beentry->st_session.idle_count += st_session_diff.idle_count;
+
+		beentry->st_session.idle_in_transaction_time += st_session_diff.idle_in_transaction_time;
+		beentry->st_session.idle_in_transaction_count += st_session_diff.idle_in_transaction_count;
+
+		beentry->st_session.idle_in_transaction_aborted_time += st_session_diff.idle_in_transaction_aborted_time;
+		beentry->st_session.idle_in_transaction_aborted_count += st_session_diff.idle_in_transaction_aborted_count;
+	}
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 60a397dc56..ba9ff1a2d6 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -296,6 +296,76 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }
 
+/*
+ * Returns accumulated statistics of current PG backends.
+ */
+Datum
+pg_stat_get_session(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_GET_SESSION_COLS	9
+	int			num_backends = pgstat_fetch_stat_numbackends();
+	int			curr_backend;
+	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	InitMaterializedSRF(fcinfo, 0);
+
+	/* 1-based index */
+	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
+	{
+		/* for each row */
+		Datum		values[PG_STAT_GET_SESSION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SESSION_COLS] = {0};
+		LocalPgBackendStatus *local_beentry;
+		PgBackendStatus *beentry;
+
+		/* Get the next one in the list */
+		local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
+		beentry = &local_beentry->backendStatus;
+
+		/* Report statistics only for client backends */
+		if (beentry->st_backendType != B_BACKEND)
+			continue;
+
+		/* If looking for specific PID, ignore all the others */
+		if (pid != -1 && beentry->st_procpid != pid)
+			continue;
+
+		/* Values available to all callers */
+		values[0] = Int32GetDatum(beentry->st_procpid);
+
+		/* Values only available to role member or pg_read_all_stats */
+		if (HAS_PGSTAT_PERMISSIONS(beentry->st_userid)){
+			/* convert to msec */
+			values[1] = Float8GetDatum(beentry->st_session.active_time / 1000.0);
+			values[2] = Int64GetDatum(beentry->st_session.active_count);
+			values[3] = Float8GetDatum(beentry->st_session.idle_time / 1000.0);
+			values[4] = Int64GetDatum(beentry->st_session.idle_count);
+			values[5] = Float8GetDatum(beentry->st_session.idle_in_transaction_time / 1000.0);
+			values[6] = Int64GetDatum(beentry->st_session.idle_in_transaction_count);
+			values[7] = Float8GetDatum(beentry->st_session.idle_in_transaction_aborted_time / 1000.0);
+			values[8] = Int64GetDatum(beentry->st_session.idle_in_transaction_aborted_count);
+		} else {
+			nulls[1] = true;
+			nulls[2] = true;
+			nulls[3] = true;
+			nulls[4] = true;
+			nulls[5] = true;
+			nulls[6] = true;
+			nulls[7] = true;
+			nulls[8] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+
+		/* If only a single backend was requested, and we found it, break. */
+		if (pid != -1)
+			break;
+	}
+
+	return (Datum) 0;
+}
+
 /*
  * Returns activity of PG backends.
  */
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index cbbe8acd38..f017de6779 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5559,6 +5559,15 @@
   proargtypes => '', proallargtypes => '{text,text,text}',
   proargmodes => '{o,o,o}', proargnames => '{type,name,description}',
   prosrc => 'pg_get_wait_events' },
+{ oid => '2173',
+  descr => 'statistics: cumulative information about currently active client backends',
+  proname => 'pg_stat_get_session', prorows => '100', proisstrict => 'f',
+  proretset => 't', provolatile => 's', proparallel => 'r',
+  prorettype => 'record', proargtypes => 'int4',
+  proallargtypes => '{int4,int4,float8,int8,float8,int8,float8,int8,float8,int8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,pid,active_time,active_count,idle_time,idle_count,idle_in_transaction_time,idle_in_transaction_count,idle_in_transaction_aborted_time,idle_in_transaction_aborted_count}',
+  prosrc => 'pg_stat_get_session' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
   proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 97874300c3..b2583b2824 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -81,6 +81,24 @@ typedef struct PgBackendGSSStatus
 
 } PgBackendGSSStatus;
 
+/*
+ * PgBackendSessionStatus
+ *
+ * For each session, we keep counters accumulated since the start of the session
+ * in a separate struct. The struct is always filled.
+ *
+ */
+typedef struct PgBackendSessionStatus
+{
+	int64		active_time;
+	int64		active_count;
+	int64		idle_time;
+	int64		idle_count;
+	int64		idle_in_transaction_time;
+	int64		idle_in_transaction_count;
+	int64		idle_in_transaction_aborted_time;
+	int64		idle_in_transaction_aborted_count;
+} PgBackendSessionStatus;
 
 /* ----------
  * PgBackendStatus
@@ -170,6 +188,9 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* Counters accumulated since the start of the session */
+	PgBackendSessionStatus st_session;
 } PgBackendStatus;
 
 
@@ -234,6 +255,17 @@ typedef struct PgBackendStatus
 	 ((before_changecount) & 1) == 0)
 
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLE(s) \
+	((s)->st_state == STATE_IDLE)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION)
+#define PGSTAT_IS_IDLEINTRANSACTION_ABORTED(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+
+
 /* ----------
  * LocalPgBackendStatus
  *
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 3014d047fe..f37c57e220 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2106,6 +2106,16 @@ pg_stat_replication_slots| SELECT s.slot_name,
    FROM pg_replication_slots r,
     LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset)
   WHERE (r.datoid IS NOT NULL);
+pg_stat_session| SELECT pid,
+    active_time,
+    active_count,
+    idle_time,
+    idle_count,
+    idle_in_transaction_time,
+    idle_in_transaction_count,
+    idle_in_transaction_aborted_time,
+    idle_in_transaction_aborted_count
+   FROM pg_stat_get_session(NULL::integer) s(pid, active_time, active_count, idle_time, idle_count, idle_in_transaction_time, idle_in_transaction_count, idle_in_transaction_aborted_time, idle_in_transaction_aborted_count);
 pg_stat_slru| SELECT name,
     blks_zeroed,
     blks_hit,
diff --git a/src/test/regress/expected/sysviews.out b/src/test/regress/expected/sysviews.out
index 91089ac215..308780f119 100644
--- a/src/test/regress/expected/sysviews.out
+++ b/src/test/regress/expected/sysviews.out
@@ -223,3 +223,42 @@ select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
  t
 (1 row)
 
+select active_count as prev_active_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select active_count from pg_stat_session where pid = pg_backend_pid()) - :prev_active_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_in_transaction_count as prev_idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+commit;
+select (select idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_in_transaction_aborted_count as prev_idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+do $$
+begin
+raise 'test error';
+end;
+$$ language plpgsql;
+ERROR:  test error
+CONTEXT:  PL/pgSQL function inline_code_block line 3 at RAISE
+rollback;
+select (select idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_aborted_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
diff --git a/src/test/regress/sql/sysviews.sql b/src/test/regress/sql/sysviews.sql
index b2a7923754..cfa69a8975 100644
--- a/src/test/regress/sql/sysviews.sql
+++ b/src/test/regress/sql/sysviews.sql
@@ -98,3 +98,24 @@ set timezone_abbreviations = 'Australia';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
 set timezone_abbreviations = 'India';
 select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
+
+select active_count as prev_active_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select active_count from pg_stat_session where pid = pg_backend_pid()) - :prev_active_count = 1 as ok;
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+
+select idle_in_transaction_count as prev_idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+commit;
+select (select idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_count = 1 as ok;
+
+select idle_in_transaction_aborted_count as prev_idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+do $$
+begin
+raise 'test error';
+end;
+$$ language plpgsql;
+rollback;
+select (select idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_aborted_count = 1 as ok;
\ No newline at end of file
-- 
2.34.1

From 4974c8c9440bbd6d7f9e37e882990602d69b495f Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@gmail.com>
Date: Mon, 3 Mar 2025 13:19:56 +0100
Subject: [PATCH] Adds pg_stat_session view to track statistics accumulated
 during  lifetime of a session (client backend).

catversion bump is necessary due to a new view / function

Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, Atsushi
Torikoshi, and Andrei Zubkov

Discussion:
https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
 doc/src/sgml/monitoring.sgml                | 134 ++++++++++++++++++++
 src/backend/catalog/system_views.sql        |  13 ++
 src/backend/utils/activity/backend_status.c |  64 ++++++++--
 src/backend/utils/adt/pgstatfuncs.c         |  70 ++++++++++
 src/include/catalog/pg_proc.dat             |   9 ++
 src/include/utils/backend_status.h          |  32 +++++
 src/test/regress/expected/rules.out         |  10 ++
 src/test/regress/expected/sysviews.out      |  39 ++++++
 src/test/regress/sql/sysviews.sql           |  21 +++
 9 files changed, 379 insertions(+), 13 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 9178f1d34e..2f4b77ca52 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -414,6 +414,20 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
        See <xref linkend="copy-progress-reporting"/>.
       </entry>
      </row>
+
+     <row>
+      <entry>
+       <structname>pg_stat_session</structname>
+       <indexterm><primary>pg_stat_session</primary></indexterm>
+      </entry>
+      <entry>
+       One row per client backend, showing information related to
+       the currently accumulated activity of that process, such as time spent in
+       a certain state.
+       See <link linkend="monitoring-pg-stat-session-view">
+       <structname>pg_stat_session</structname></link> for details.
+      </entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
@@ -4772,6 +4786,110 @@ description | Waiting for a newly initialized WAL file to reach durable storage
    </tgroup>
   </table>
 
+  <table id="monitoring-pg-stat-session-view" xreflabel="pg_stat_session">
+   <title><structname>pg_stat_session</structname> View</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>pid</structfield> <type>integer</type>
+      </para>
+      <para>
+       Process ID of this client backend.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+    <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>active_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>running</literal> or <literal>fastpath</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle</literal> state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Time in milliseconds this backend spent in the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>idle_in_transaction_aborted_count</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times this backend switched to the <literal>idle in transaction (aborted)</literal>
+       state.
+      </para></entry>
+     </row>
+
+    </tbody>
+   </tgroup>
+  </table>
+
  </sect2>
 
  <sect2 id="monitoring-stats-functions">
@@ -5277,6 +5395,22 @@ FROM pg_stat_get_backend_idset() AS backendid;
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_get_session</primary>
+        </indexterm>
+        <function>pg_stat_get_session</function> ( <type>integer</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Returns a row, showing statistics about the client backend with the
+        specified process ID, or one row per client backend
+        if <literal>NULL</literal> is specified. The fields returned are the
+        same as those of <structname>pg_stat_session</structname> view.
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index a4d2cfdcaf..0f191c9b8e 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -895,6 +895,19 @@ CREATE VIEW pg_stat_activity AS
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
 
+CREATE VIEW pg_stat_session AS
+    SELECT
+            s.pid,
+            s.active_time,
+            s.active_count,
+            s.idle_time,
+            s.idle_count,
+            s.idle_in_transaction_time,
+            s.idle_in_transaction_count,
+            s.idle_in_transaction_aborted_time,
+            s.idle_in_transaction_aborted_count
+     FROM pg_stat_get_session(NULL) as s;
+
 CREATE VIEW pg_stat_replication AS
     SELECT
             S.pid,
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 5f68ef26ad..d0c66f6d93 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -317,6 +317,8 @@ pgstat_bestart(void)
 	lbeentry.st_xact_start_timestamp = 0;
 	lbeentry.st_databaseid = MyDatabaseId;
 
+	MemSet(&lbeentry.st_session, 0, sizeof(lbeentry.st_session));
+
 	/* We have userid for client-backends, wal-sender and bgworker processes */
 	if (lbeentry.st_backendType == B_BACKEND
 		|| lbeentry.st_backendType == B_WAL_SENDER
@@ -509,6 +511,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	TimestampTz current_timestamp;
 	int			len = 0;
 
+	PgBackendSessionStatus st_session_diff;
+	MemSet(&st_session_diff, 0, sizeof(st_session_diff));
+
 	TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
 
 	if (!beentry)
@@ -534,6 +539,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
+			MemSet(&beentry->st_session, 0, sizeof(beentry->st_session));
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
 		return;
@@ -556,27 +562,45 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	current_timestamp = GetCurrentTimestamp();
 
 	/*
-	 * If the state has changed from "active" or "idle in transaction",
-	 * calculate the duration.
+	 * If a client backend has changed state, update per-database and per-session counters.
 	 */
-	if ((beentry->st_state == STATE_RUNNING ||
-		 beentry->st_state == STATE_FASTPATH ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION ||
-		 beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
-		state != beentry->st_state)
+	if ((PGSTAT_IS_ACTIVE(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+		 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry) ||
+		 PGSTAT_IS_IDLE(beentry)) &&
+		state != beentry->st_state &&
+		beentry->st_backendType == B_BACKEND)
 	{
 		long		secs;
 		int			usecs;
+		int64		usecs_diff;
 
 		TimestampDifference(beentry->st_state_start_timestamp,
 							current_timestamp,
 							&secs, &usecs);
-
-		if (beentry->st_state == STATE_RUNNING ||
-			beentry->st_state == STATE_FASTPATH)
-			pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
-		else
-			pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+		usecs_diff = secs * 1000000 + usecs;
+
+		/* compute values for pg_stat_database */
+		if (PGSTAT_IS_ACTIVE(beentry))
+			pgstat_count_conn_active_time((PgStat_Counter) usecs_diff);
+		else if (PGSTAT_IS_IDLEINTRANSACTION(beentry) ||
+				 PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry))
+			pgstat_count_conn_txn_idle_time((PgStat_Counter) usecs_diff);
+
+		/* compute values for pg_stat_session */
+		if (PGSTAT_IS_ACTIVE(beentry)) {
+			st_session_diff.active_time = usecs_diff;
+			st_session_diff.active_count += 1;
+		} else if (PGSTAT_IS_IDLE(beentry)){
+			st_session_diff.idle_time = usecs_diff;
+			st_session_diff.idle_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION(beentry)){
+			st_session_diff.idle_in_transaction_time = usecs_diff;
+			st_session_diff.idle_in_transaction_count += 1;
+		} else if (PGSTAT_IS_IDLEINTRANSACTION_ABORTED(beentry)){
+			st_session_diff.idle_in_transaction_aborted_time = usecs_diff;
+			st_session_diff.idle_in_transaction_aborted_count += 1;
+		}
 	}
 
 	/*
@@ -602,6 +626,20 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 		beentry->st_activity_start_timestamp = start_timestamp;
 	}
 
+	if (beentry->st_backendType == B_BACKEND) {
+		beentry->st_session.active_time += st_session_diff.active_time;
+		beentry->st_session.active_count += st_session_diff.active_count;
+
+		beentry->st_session.idle_time += st_session_diff.idle_time;
+		beentry->st_session.idle_count += st_session_diff.idle_count;
+
+		beentry->st_session.idle_in_transaction_time += st_session_diff.idle_in_transaction_time;
+		beentry->st_session.idle_in_transaction_count += st_session_diff.idle_in_transaction_count;
+
+		beentry->st_session.idle_in_transaction_aborted_time += st_session_diff.idle_in_transaction_aborted_time;
+		beentry->st_session.idle_in_transaction_aborted_count += st_session_diff.idle_in_transaction_aborted_count;
+	}
+
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 0212d8d590..8a8d185793 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -324,6 +324,76 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }
 
+/*
+ * Returns accumulated statistics of current PG backends.
+ */
+Datum
+pg_stat_get_session(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_GET_SESSION_COLS	9
+	int			num_backends = pgstat_fetch_stat_numbackends();
+	int			curr_backend;
+	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	InitMaterializedSRF(fcinfo, 0);
+
+	/* 1-based index */
+	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
+	{
+		/* for each row */
+		Datum		values[PG_STAT_GET_SESSION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SESSION_COLS] = {0};
+		LocalPgBackendStatus *local_beentry;
+		PgBackendStatus *beentry;
+
+		/* Get the next one in the list */
+		local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
+		beentry = &local_beentry->backendStatus;
+
+		/* Report statistics only for client backends */
+		if (beentry->st_backendType != B_BACKEND)
+			continue;
+
+		/* If looking for specific PID, ignore all the others */
+		if (pid != -1 && beentry->st_procpid != pid)
+			continue;
+
+		/* Values available to all callers */
+		values[0] = Int32GetDatum(beentry->st_procpid);
+
+		/* Values only available to role member or pg_read_all_stats */
+		if (HAS_PGSTAT_PERMISSIONS(beentry->st_userid)){
+			/* convert to msec */
+			values[1] = Float8GetDatum(beentry->st_session.active_time / 1000.0);
+			values[2] = Int64GetDatum(beentry->st_session.active_count);
+			values[3] = Float8GetDatum(beentry->st_session.idle_time / 1000.0);
+			values[4] = Int64GetDatum(beentry->st_session.idle_count);
+			values[5] = Float8GetDatum(beentry->st_session.idle_in_transaction_time / 1000.0);
+			values[6] = Int64GetDatum(beentry->st_session.idle_in_transaction_count);
+			values[7] = Float8GetDatum(beentry->st_session.idle_in_transaction_aborted_time / 1000.0);
+			values[8] = Int64GetDatum(beentry->st_session.idle_in_transaction_aborted_count);
+		} else {
+			nulls[1] = true;
+			nulls[2] = true;
+			nulls[3] = true;
+			nulls[4] = true;
+			nulls[5] = true;
+			nulls[6] = true;
+			nulls[7] = true;
+			nulls[8] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+
+		/* If only a single backend was requested, and we found it, break. */
+		if (pid != -1)
+			break;
+	}
+
+	return (Datum) 0;
+}
+
 /*
  * Returns activity of PG backends.
  */
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index cd9422d0ba..f78d9a8c45 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5584,6 +5584,15 @@
   proargtypes => '', proallargtypes => '{text,text,text}',
   proargmodes => '{o,o,o}', proargnames => '{type,name,description}',
   prosrc => 'pg_get_wait_events' },
+{ oid => '2173',
+  descr => 'statistics: cumulative information about currently active client backends',
+  proname => 'pg_stat_get_session', prorows => '100', proisstrict => 'f',
+  proretset => 't', provolatile => 's', proparallel => 'r',
+  prorettype => 'record', proargtypes => 'int4',
+  proallargtypes => '{int4,int4,float8,int8,float8,int8,float8,int8,float8,int8}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{pid,pid,active_time,active_count,idle_time,idle_count,idle_in_transaction_time,idle_in_transaction_count,idle_in_transaction_aborted_time,idle_in_transaction_aborted_count}',
+  prosrc => 'pg_stat_get_session' },
 { oid => '3318',
   descr => 'statistics: information about progress of backends running maintenance command',
   proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index d3d4ff6c5c..a04c3581d6 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -81,6 +81,24 @@ typedef struct PgBackendGSSStatus
 
 } PgBackendGSSStatus;
 
+/*
+ * PgBackendSessionStatus
+ *
+ * For each session, we keep counters accumulated since the start of the session
+ * in a separate struct. The struct is always filled.
+ *
+ */
+typedef struct PgBackendSessionStatus
+{
+	int64		active_time;
+	int64		active_count;
+	int64		idle_time;
+	int64		idle_count;
+	int64		idle_in_transaction_time;
+	int64		idle_in_transaction_count;
+	int64		idle_in_transaction_aborted_time;
+	int64		idle_in_transaction_aborted_count;
+} PgBackendSessionStatus;
 
 /* ----------
  * PgBackendStatus
@@ -170,6 +188,9 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* Counters accumulated since the start of the session */
+	PgBackendSessionStatus st_session;
 } PgBackendStatus;
 
 
@@ -234,6 +255,17 @@ typedef struct PgBackendStatus
 	 ((before_changecount) & 1) == 0)
 
 
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+	((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLE(s) \
+	((s)->st_state == STATE_IDLE)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION)
+#define PGSTAT_IS_IDLEINTRANSACTION_ABORTED(s) \
+	((s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
+
+
 /* ----------
  * LocalPgBackendStatus
  *
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 62f69ac20b..81b6de5935 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -2114,6 +2114,16 @@ pg_stat_replication_slots| SELECT s.slot_name,
    FROM pg_replication_slots r,
     LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset)
   WHERE (r.datoid IS NOT NULL);
+pg_stat_session| SELECT pid,
+    active_time,
+    active_count,
+    idle_time,
+    idle_count,
+    idle_in_transaction_time,
+    idle_in_transaction_count,
+    idle_in_transaction_aborted_time,
+    idle_in_transaction_aborted_count
+   FROM pg_stat_get_session(NULL::integer) s(pid, active_time, active_count, idle_time, idle_count, idle_in_transaction_time, idle_in_transaction_count, idle_in_transaction_aborted_time, idle_in_transaction_aborted_count);
 pg_stat_slru| SELECT name,
     blks_zeroed,
     blks_hit,
diff --git a/src/test/regress/expected/sysviews.out b/src/test/regress/expected/sysviews.out
index 83228cfca2..51fd9bee6d 100644
--- a/src/test/regress/expected/sysviews.out
+++ b/src/test/regress/expected/sysviews.out
@@ -232,3 +232,42 @@ select * from pg_timezone_abbrevs where abbrev = 'LMT';
  LMT    | @ 7 hours 52 mins 58 secs ago | f
 (1 row)
 
+select active_count as prev_active_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select active_count from pg_stat_session where pid = pg_backend_pid()) - :prev_active_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_in_transaction_count as prev_idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+commit;
+select (select idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
+select idle_in_transaction_aborted_count as prev_idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+do $$
+begin
+raise 'test error';
+end;
+$$ language plpgsql;
+ERROR:  test error
+CONTEXT:  PL/pgSQL function inline_code_block line 3 at RAISE
+rollback;
+select (select idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_aborted_count = 1 as ok;
+ ok 
+----
+ t
+(1 row)
+
diff --git a/src/test/regress/sql/sysviews.sql b/src/test/regress/sql/sysviews.sql
index 66179f026b..b90a911d81 100644
--- a/src/test/regress/sql/sysviews.sql
+++ b/src/test/regress/sql/sysviews.sql
@@ -101,3 +101,24 @@ select count(distinct utc_offset) >= 24 as ok from pg_timezone_abbrevs;
 -- One specific case we can check without much fear of breakage
 -- is the historical local-mean-time value used for America/Los_Angeles.
 select * from pg_timezone_abbrevs where abbrev = 'LMT';
+
+select active_count as prev_active_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select active_count from pg_stat_session where pid = pg_backend_pid()) - :prev_active_count = 1 as ok;
+
+select idle_count as prev_idle_count from pg_stat_session where pid = pg_backend_pid() \gset
+select (select idle_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_count = 1 as ok;
+
+select idle_in_transaction_count as prev_idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+commit;
+select (select idle_in_transaction_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_count = 1 as ok;
+
+select idle_in_transaction_aborted_count as prev_idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid() \gset
+begin;
+do $$
+begin
+raise 'test error';
+end;
+$$ language plpgsql;
+rollback;
+select (select idle_in_transaction_aborted_count from pg_stat_session where pid = pg_backend_pid()) - :prev_idle_in_transaction_aborted_count = 1 as ok;
-- 
2.34.1