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Change memory-space accounting mechanism in tuplesort.c and tuplestore.c
to make a reasonable attempt at accounting for palloc overhead, not just the requested size of each memory chunk. Since in many scenarios this will make for a significant reduction in the amount of space acquired, partially compensate by doubling the default value of SORT_MEM to 1Mb. Per discussion in pgsql-general around 9-Jun-2002..
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-133
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10 files changed

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‎doc/src/sgml/runtime.sgml

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@@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.123 2002/08/09 22:52:04 petere Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.124 2002/08/12 00:36:11 tgl Exp $
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-->
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<Chapter Id="runtime">
@@ -1640,8 +1640,8 @@ dynamic_library_path = '/usr/local/lib/postgresql:/home/my_project/lib:$libdir'
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<para>
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Specifies the amount of memory to be used by internal sorts and
16421642
hashes before switching to temporary disk files. The value is
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specified in kilobytes, and defaults to 512 kilobytes. Note that
1644-
for a complex query, several sorts and/or hashes might be
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specified in kilobytes, and defaults to 1024 kilobytes (1MB).
1644+
Note that for a complex query, several sorts and/or hashes might be
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running in parallel, and each one will be allowed to use as much
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memory as this value specifies before it starts to put data into
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temporary files. Also, each running backend could be doing one

‎src/backend/utils/init/globals.c

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@@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/init/globals.c,v 1.65 2002/06/20 20:29:40 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/init/globals.c,v 1.66 2002/08/12 00:36:11 tgl Exp $
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*
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* NOTES
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* Globals used all over the place should be declared here and not
@@ -71,6 +71,6 @@ char FloatFormat[20] = "%f";
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bool enableFsync = true;
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bool allowSystemTableMods = false;
74-
int SortMem = 512;
74+
int SortMem = 1024;
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int VacuumMem = 8192;
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int NBuffers = DEF_NBUFFERS;

‎src/backend/utils/misc/guc.c

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Original file line numberDiff line numberDiff line change
@@ -5,7 +5,7 @@
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* command, configuration file, and command line options.
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* See src/backend/utils/misc/README for more information.
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*
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* $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.78 2002/08/07 17:26:24 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.79 2002/08/12 00:36:11 tgl Exp $
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*
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* Copyright 2000 by PostgreSQL Global Development Group
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* Written by Peter Eisentraut <peter_e@gmx.net>.
@@ -556,7 +556,7 @@ static struct config_int
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557557
{
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{ "sort_mem", PGC_USERSET }, &SortMem,
559-
512, 4 * BLCKSZ / 1024, INT_MAX, NULL, NULL
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1024, 8 * BLCKSZ / 1024, INT_MAX, NULL, NULL
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},
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{

‎src/backend/utils/misc/postgresql.conf.sample

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -57,7 +57,7 @@
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#
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# Non-shared Memory Sizes
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#
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#sort_mem = 512 # min 32
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#sort_mem = 1024 # min 64
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#vacuum_mem = 8192 # min 1024
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‎src/backend/utils/mmgr/aset.c

Lines changed: 19 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -11,7 +11,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/mmgr/aset.c,v 1.46 2002/06/20 20:29:40 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/mmgr/aset.c,v 1.47 2002/08/12 00:36:12 tgl Exp $
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*
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* NOTE:
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* This is a new (Feb. 05, 1999) implementation of the allocation set
@@ -204,11 +204,11 @@ static void *AllocSetRealloc(MemoryContext context, void *pointer, Size size);
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static void AllocSetInit(MemoryContext context);
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static void AllocSetReset(MemoryContext context);
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static void AllocSetDelete(MemoryContext context);
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static Size AllocSetGetChunkSpace(MemoryContext context, void *pointer);
208+
static void AllocSetStats(MemoryContext context);
208209
#ifdef MEMORY_CONTEXT_CHECKING
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static void AllocSetCheck(MemoryContext context);
210211
#endif
211-
static void AllocSetStats(MemoryContext context);
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/*
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* This is the virtual function table for AllocSet contexts.
@@ -220,10 +220,11 @@ static MemoryContextMethods AllocSetMethods = {
220220
AllocSetInit,
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AllocSetReset,
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AllocSetDelete,
223+
AllocSetGetChunkSpace,
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AllocSetStats
223225
#ifdef MEMORY_CONTEXT_CHECKING
224-
AllocSetCheck,
226+
, AllocSetCheck
225227
#endif
226-
AllocSetStats
227228
};
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229230

@@ -953,6 +954,19 @@ AllocSetRealloc(MemoryContext context, void *pointer, Size size)
953954
}
954955
}
955956

957+
/*
958+
* AllocSetGetChunkSpace
959+
* Given a currently-allocated chunk, determine the total space
960+
* it occupies (including all memory-allocation overhead).
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*/
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static Size
963+
AllocSetGetChunkSpace(MemoryContext context, void *pointer)
964+
{
965+
AllocChunk chunk = AllocPointerGetChunk(pointer);
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return chunk->size + ALLOC_CHUNKHDRSZ;
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}
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/*
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* AllocSetStats
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* Displays stats about memory consumption of an allocset.

‎src/backend/utils/mmgr/mcxt.c

Lines changed: 34 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -14,7 +14,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/mmgr/mcxt.c,v 1.31 2002/08/10 20:29:18 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/mmgr/mcxt.c,v 1.32 2002/08/12 00:36:12 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
@@ -224,6 +224,39 @@ MemoryContextResetAndDeleteChildren(MemoryContext context)
224224
(*context->methods->reset) (context);
225225
}
226226

227+
/*
228+
* GetMemoryChunkSpace
229+
* Given a currently-allocated chunk, determine the total space
230+
* it occupies (including all memory-allocation overhead).
231+
*
232+
* This is useful for measuring the total space occupied by a set of
233+
* allocated chunks.
234+
*/
235+
Size
236+
GetMemoryChunkSpace(void *pointer)
237+
{
238+
StandardChunkHeader *header;
239+
240+
/*
241+
* Try to detect bogus pointers handed to us, poorly though we can.
242+
* Presumably, a pointer that isn't MAXALIGNED isn't pointing at an
243+
* allocated chunk.
244+
*/
245+
Assert(pointer != NULL);
246+
Assert(pointer == (void *) MAXALIGN(pointer));
247+
248+
/*
249+
* OK, it's probably safe to look at the chunk header.
250+
*/
251+
header = (StandardChunkHeader *)
252+
((char *) pointer - STANDARDCHUNKHEADERSIZE);
253+
254+
AssertArg(MemoryContextIsValid(header->context));
255+
256+
return (*header->context->methods->get_chunk_space) (header->context,
257+
pointer);
258+
}
259+
227260
/*
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* MemoryContextStats
229262
* Print statistics about the named context and all its descendants.

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