diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml index 1f70fd4..b630bc8 100644 *** a/doc/src/sgml/monitoring.sgml --- b/doc/src/sgml/monitoring.sgml *************** postgres: user + + + pg_stat_reset_shared() + text + + Reset some of the shared statistics counters for the database cluster to + zero (requires superuser privileges). Calling + pg_stat_reset_shared('bgwriter') will zero all the values shown by + pg_stat_bgwriter. + + diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c index 4fd2abf..7335a50 100644 *** a/src/backend/postmaster/pgstat.c --- b/src/backend/postmaster/pgstat.c *************** static void pgstat_recv_tabstat(PgStat_M *** 270,275 **** --- 270,276 ---- static void pgstat_recv_tabpurge(PgStat_MsgTabpurge *msg, int len); static void pgstat_recv_dropdb(PgStat_MsgDropdb *msg, int len); static void pgstat_recv_resetcounter(PgStat_MsgResetcounter *msg, int len); + static void pgstat_recv_resetsharedcounter(PgStat_MsgResetsharedcounter *msg, int len); static void pgstat_recv_autovac(PgStat_MsgAutovacStart *msg, int len); static void pgstat_recv_vacuum(PgStat_MsgVacuum *msg, int len); static void pgstat_recv_analyze(PgStat_MsgAnalyze *msg, int len); *************** pgstat_reset_counters(void) *** 1153,1158 **** --- 1154,1190 ---- pgstat_send(&msg, sizeof(msg)); } + /* ---------- + * pgstat_reset_shared_counters() - + * + * Tell the statistics collector to reset cluster-wide shared counters. + * ---------- + */ + void + pgstat_reset_shared_counters(const char *target) + { + PgStat_MsgResetsharedcounter msg; + + if (pgStatSock < 0) + return; + + if (!superuser()) + ereport(ERROR, + (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), + errmsg("must be superuser to reset statistics counters"))); + + if (strcmp(target, "bgwriter") == 0) + msg.m_resettarget = RESET_BGWRITER; + else + { + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("Unrecognized reset target"))); + } + + pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_RESETSHAREDCOUNTER); + pgstat_send(&msg, sizeof(msg)); + } /* ---------- * pgstat_report_autovac() - *************** PgstatCollectorMain(int argc, char *argv *** 2915,2920 **** --- 2947,2958 ---- len); break; + case PGSTAT_MTYPE_RESETSHAREDCOUNTER: + pgstat_recv_resetsharedcounter( + (PgStat_MsgResetsharedcounter *) &msg, + len); + break; + case PGSTAT_MTYPE_AUTOVAC_START: pgstat_recv_autovac((PgStat_MsgAutovacStart *) &msg, len); break; *************** pgstat_recv_resetcounter(PgStat_MsgReset *** 3869,3874 **** --- 3907,3930 ---- } /* ---------- + * pgstat_recv_resetshared() - + * + * Reset some shared statistics of the cluster. + * ---------- + */ + static void + pgstat_recv_resetsharedcounter(PgStat_MsgResetsharedcounter *msg, int len) + { + if (msg->m_resettarget==RESET_BGWRITER) + { + /* Reset the global background writer statistics for the cluster. */ + memset(&globalStats, 0, sizeof(globalStats)); + } + /* Presumably the sender of this message validated the target, don't + complain here if it's not valid */ + } + + /* ---------- * pgstat_recv_autovac() - * * Process an autovacuum signalling message. diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c index ab741ca..e5bc95a 100644 *** a/src/backend/utils/adt/pgstatfuncs.c --- b/src/backend/utils/adt/pgstatfuncs.c *************** extern Datum pg_stat_get_buf_alloc(PG_FU *** 78,83 **** --- 78,84 ---- extern Datum pg_stat_clear_snapshot(PG_FUNCTION_ARGS); extern Datum pg_stat_reset(PG_FUNCTION_ARGS); + extern Datum pg_stat_reset_shared(PG_FUNCTION_ARGS); /* Global bgwriter statistics, from bgwriter.c */ extern PgStat_MsgBgWriter bgwriterStats; *************** pg_stat_reset(PG_FUNCTION_ARGS) *** 1108,1110 **** --- 1109,1123 ---- PG_RETURN_VOID(); } + + /* Reset some shared cluster-wide counters */ + Datum + pg_stat_reset_shared(PG_FUNCTION_ARGS) + { + char *target; + target = TextDatumGetCString(PG_GETARG_DATUM(0)); + + pgstat_reset_shared_counters(target); + + PG_RETURN_VOID(); + } diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h index a8efed9..87072fc 100644 *** a/src/include/catalog/pg_proc.h --- b/src/include/catalog/pg_proc.h *************** DATA(insert OID = 2230 ( pg_stat_clear_ *** 3071,3076 **** --- 3071,3078 ---- DESCR("statistics: discard current transaction's statistics snapshot"); DATA(insert OID = 2274 ( pg_stat_reset PGNSP PGUID 12 1 0 0 f f f f f v 0 0 2278 "" _null_ _null_ _null_ _null_ pg_stat_reset _null_ _null_ _null_ )); DESCR("statistics: reset collected statistics for current database"); + DATA(insert OID = 3775 ( pg_stat_reset_shared PGNSP PGUID 12 1 0 0 f f f f f v 1 0 2278 "25" _null_ _null_ _null_ _null_ pg_stat_reset_shared _null_ _null_ _null_ )); + DESCR("statistics: reset collected statistics shared across the cluster"); DATA(insert OID = 1946 ( encode PGNSP PGUID 12 1 0 0 f f f t f i 2 0 25 "17 25" _null_ _null_ _null_ _null_ binary_encode _null_ _null_ _null_ )); DESCR("convert bytea value into some ascii-only text string"); diff --git a/src/include/pgstat.h b/src/include/pgstat.h index 3cc334c..c3de665 100644 *** a/src/include/pgstat.h --- b/src/include/pgstat.h *************** typedef enum StatMsgType *** 38,43 **** --- 38,44 ---- PGSTAT_MTYPE_TABPURGE, PGSTAT_MTYPE_DROPDB, PGSTAT_MTYPE_RESETCOUNTER, + PGSTAT_MTYPE_RESETSHAREDCOUNTER, PGSTAT_MTYPE_AUTOVAC_START, PGSTAT_MTYPE_VACUUM, PGSTAT_MTYPE_ANALYZE, *************** typedef struct PgStat_TableCounts *** 93,98 **** --- 94,105 ---- PgStat_Counter t_blocks_hit; } PgStat_TableCounts; + /* Possible targets for resetting cluster-wide shared values */ + typedef enum PgStat_Shared_Reset_Target + { + RESET_BGWRITER + } PgStat_Shared_Reset_Target; + /* ------------------------------------------------------------ * Structures kept in backend local memory while accumulating counts *************** typedef struct PgStat_MsgResetcounter *** 260,265 **** --- 267,282 ---- Oid m_databaseid; } PgStat_MsgResetcounter; + /* ---------- + * PgStat_MsgResetsharedcounter Sent by the backend to tell the collector + * to reset a shared counter + * ---------- + */ + typedef struct PgStat_MsgResetsharedcounter + { + PgStat_MsgHdr m_hdr; + PgStat_Shared_Reset_Target m_resettarget; + } PgStat_MsgResetsharedcounter; /* ---------- * PgStat_MsgAutovacStart Sent by the autovacuum daemon to signal *************** typedef union PgStat_Msg *** 414,419 **** --- 431,437 ---- PgStat_MsgTabpurge msg_tabpurge; PgStat_MsgDropdb msg_dropdb; PgStat_MsgResetcounter msg_resetcounter; + PgStat_MsgResetsharedcounter msg_resetsharedcounter; PgStat_MsgAutovacStart msg_autovacuum; PgStat_MsgVacuum msg_vacuum; PgStat_MsgAnalyze msg_analyze; *************** extern void pgstat_drop_database(Oid dat *** 635,640 **** --- 653,659 ---- extern void pgstat_clear_snapshot(void); extern void pgstat_reset_counters(void); + extern void pgstat_reset_shared_counters(const char *); extern void pgstat_report_autovac(Oid dboid); extern void pgstat_report_vacuum(Oid tableoid, bool shared, bool adopt_counts,