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Shared-memory hashtables have non-extensible directories, which means

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it's a good idea to choose the directory size based on the expected
number of entries.  But ShmemInitHash was using a hard-wired constant.
Boo hiss.  This accounts for recent report of postmaster failure when
asking for 64K or more buffers.
This commit is contained in:
Tom Lane
2000-02-26 05:25:55 +00:00
parent c05abfb1a8
commit 08b1040374
3 changed files with 53 additions and 25 deletions
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16
src/backend/storage/ipc/shmem.c
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@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/shmem.c,v 1.48 2000/01/26 05:56:58 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/shmem.c,v 1.49 2000/02/26 05:25:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -332,7 +332,7 @@ ShmemIsValid(unsigned long addr)
HTAB *
ShmemInitHash(char *name, /* table string name for shmem index */
long init_size, /* initial table size */
long max_size, /* max size of the table (NOT USED) */
long max_size, /* max size of the table */
HASHCTL *infoP, /* info about key and bucket size */
int hash_flags) /* info about infoP */
{
@@ -340,19 +340,21 @@ ShmemInitHash(char *name, /* table string name for shmem index */
long *location;
/*
* Hash tables allocated in shared memory have a fixed directory; it
* can't grow or other backends wouldn't be able to find it. The
* segbase is for calculating pointer values. The shared memory
* Hash tables allocated in shared memory have a fixed directory;
* it can't grow or other backends wouldn't be able to find it.
* So, make sure we make it big enough to start with.
*
* The segbase is for calculating pointer values. The shared memory
* allocator must be specified too.
*/
infoP->dsize = infoP->max_dsize = DEF_DIRSIZE;
infoP->dsize = infoP->max_dsize = hash_select_dirsize(max_size);
infoP->segbase = (long *) ShmemBase;
infoP->alloc = ShmemAlloc;
hash_flags |= HASH_SHARED_MEM | HASH_DIRSIZE;
/* look it up in the shmem index */
location = ShmemInitStruct(name,
sizeof(HHDR) + DEF_DIRSIZE * sizeof(SEG_OFFSET),
sizeof(HHDR) + infoP->dsize * sizeof(SEG_OFFSET),
&found);
/*