From e9134ad5465d0dae626cf658def2ca58648d64c2 Mon Sep 17 00:00:00 2001 From: Melih Mutlu Date: Tue, 13 Jun 2023 15:00:05 +0300 Subject: [PATCH v2] Adding id/parent_id into pg_backend_memory_contexts Added three new fields into the tuples returned by pg_get_backend_memory_contexts() to specify the parent/child relation between memory contexts and the path from root to current context. Context names cannot be relied on since they're not unique. Therefore, unique id and parent_id are needed for each context. Those new id's are assigned during pg_get_backend_memory_contexts() call and not stored anywhere. So they may change in each pg_get_backend_memory_contexts() call and shouldn't be used across differenct pg_get_backend_memory_contexts() calls. Context id's are start from 0 which is assigned to TopMemoryContext. --- doc/src/sgml/system-views.sgml | 27 +++++++++++++ src/backend/utils/adt/mcxtfuncs.c | 59 ++++++++++++++++++++++++++--- src/include/catalog/pg_proc.dat | 6 +-- src/test/regress/expected/rules.out | 7 +++- 4 files changed, 89 insertions(+), 10 deletions(-) diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml index 57b228076e..7811130cfb 100644 --- a/doc/src/sgml/system-views.sgml +++ b/doc/src/sgml/system-views.sgml @@ -538,6 +538,33 @@ Used space in bytes + + + + context_id int4 + + + Current context id + + + + + + parent_id int4 + + + Parent context id + + + + + + path int4 + + + Path to reach the current context from TopMemoryContext + + diff --git a/src/backend/utils/adt/mcxtfuncs.c b/src/backend/utils/adt/mcxtfuncs.c index 92ca5b2f72..81cb35dd47 100644 --- a/src/backend/utils/adt/mcxtfuncs.c +++ b/src/backend/utils/adt/mcxtfuncs.c @@ -20,6 +20,7 @@ #include "mb/pg_wchar.h" #include "storage/proc.h" #include "storage/procarray.h" +#include "utils/array.h" #include "utils/builtins.h" /* ---------- @@ -28,6 +29,8 @@ */ #define MEMORY_CONTEXT_IDENT_DISPLAY_SIZE 1024 +static Datum convert_path_to_datum(List *path); + /* * PutMemoryContextsStatsTupleStore * One recursion level for pg_get_backend_memory_contexts. @@ -35,9 +38,10 @@ static void PutMemoryContextsStatsTupleStore(Tuplestorestate *tupstore, TupleDesc tupdesc, MemoryContext context, - const char *parent, int level) + const char *parent, int level, int *context_id, + int parent_id, List *path) { -#define PG_GET_BACKEND_MEMORY_CONTEXTS_COLS 9 +#define PG_GET_BACKEND_MEMORY_CONTEXTS_COLS 12 Datum values[PG_GET_BACKEND_MEMORY_CONTEXTS_COLS]; bool nulls[PG_GET_BACKEND_MEMORY_CONTEXTS_COLS]; @@ -45,6 +49,7 @@ PutMemoryContextsStatsTupleStore(Tuplestorestate *tupstore, MemoryContext child; const char *name; const char *ident; + int current_context_id = (*context_id)++; Assert(MemoryContextIsValid(context)); @@ -103,13 +108,29 @@ PutMemoryContextsStatsTupleStore(Tuplestorestate *tupstore, values[6] = Int64GetDatum(stat.freespace); values[7] = Int64GetDatum(stat.freechunks); values[8] = Int64GetDatum(stat.totalspace - stat.freespace); + values[9] = Int32GetDatum(current_context_id); + + if(parent_id < 0) + /* TopMemoryContext has no parent context */ + nulls[10] = true; + else + values[10] = Int32GetDatum(parent_id); + + if (path == NIL) + nulls[11] = true; + else + values[11] = convert_path_to_datum(path); + tuplestore_putvalues(tupstore, tupdesc, values, nulls); + path = lappend_int(path, current_context_id); for (child = context->firstchild; child != NULL; child = child->nextchild) { - PutMemoryContextsStatsTupleStore(tupstore, tupdesc, - child, name, level + 1); + PutMemoryContextsStatsTupleStore(tupstore, tupdesc, child, name, + level+1, context_id, + current_context_id, path); } + path = list_delete_last(path); } /* @@ -120,10 +141,15 @@ Datum pg_get_backend_memory_contexts(PG_FUNCTION_ARGS) { ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; + int context_id = 0; + List *path = NIL; + + elog(LOG, "pg_get_backend_memory_contexts called"); InitMaterializedSRF(fcinfo, 0); PutMemoryContextsStatsTupleStore(rsinfo->setResult, rsinfo->setDesc, - TopMemoryContext, NULL, 0); + TopMemoryContext, NULL, 0, &context_id, + -1, path); return (Datum) 0; } @@ -193,3 +219,26 @@ pg_log_backend_memory_contexts(PG_FUNCTION_ARGS) PG_RETURN_BOOL(true); } + +/* + * Convert a list of context ids to a int[] Datum + */ +static Datum +convert_path_to_datum(List *path) +{ + Datum *datum_array; + int length; + ArrayType *result_array; + ListCell *lc; + + length = list_length(path); + datum_array = (Datum *) palloc(length * sizeof(Datum)); + length = 0; + foreach(lc, path) + { + datum_array[length++] = Int32GetDatum((int) lfirst_int(lc)); + } + result_array = construct_array_builtin(datum_array, length, INT4OID); + + return PointerGetDatum(result_array); +} \ No newline at end of file diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..49514ad792 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -8212,9 +8212,9 @@ proname => 'pg_get_backend_memory_contexts', prorows => '100', proretset => 't', provolatile => 'v', proparallel => 'r', prorettype => 'record', proargtypes => '', - proallargtypes => '{text,text,text,int4,int8,int8,int8,int8,int8}', - proargmodes => '{o,o,o,o,o,o,o,o,o}', - proargnames => '{name, ident, parent, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes}', + proallargtypes => '{text,text,text,int4,int8,int8,int8,int8,int8,int4,int4,_int4}', + proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o}', + proargnames => '{name, ident, parent, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes, id, parent_id, path}', prosrc => 'pg_get_backend_memory_contexts' }, # logging memory contexts of the specified backend diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out index e07afcd4aa..c7112be09e 100644 --- a/src/test/regress/expected/rules.out +++ b/src/test/regress/expected/rules.out @@ -1311,8 +1311,11 @@ pg_backend_memory_contexts| SELECT name, total_nblocks, free_bytes, free_chunks, - used_bytes - FROM pg_get_backend_memory_contexts() pg_get_backend_memory_contexts(name, ident, parent, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes); + used_bytes, + id, + parent_id, + path + FROM pg_get_backend_memory_contexts() pg_get_backend_memory_contexts(name, ident, parent, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes, id, parent_id, path); pg_config| SELECT name, setting FROM pg_config() pg_config(name, setting); -- 2.25.1