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A catalog cache that never caches isn't much of a cache :-(. Mea culpa.

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Thanks to Brian Hirt for pointing out the performance lossage.
This commit is contained in:
Tom Lane 2000-11-24 04:16:12 +00:00
parent 48437f5c3a
commit 80dab5bd69
2 changed files with 17 additions and 15 deletions
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28
src/backend/utils/cache/catcache.c vendored
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/cache/catcache.c,v 1.72 2000/11/16 22:30:33 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/cache/catcache.c,v 1.73 2000/11/24 04:16:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -258,8 +258,8 @@ CatalogCacheInitializeCache(CatCache *cache)
&cache->cc_skey[i].sk_func);
cache->cc_skey[i].sk_nargs = cache->cc_skey[i].sk_func.fn_nargs;
/* Initialize sk_attno suitably for index scans */
cache->cc_skey[i].sk_attno = i+1;
/* Initialize sk_attno suitably for HeapKeyTest() and heap scans */
cache->cc_skey[i].sk_attno = cache->cc_key[i];
CACHE4_elog(DEBUG, "CatalogCacheInit %s %d %p",
cache->cc_relname,
@ -664,8 +664,8 @@ InitCatCache(int id,
/* ----------------
* initialize the cache's relation information for the relation
* corresponding to this cache and initialize some of the the new
* cache's other internal fields.
* corresponding to this cache, and initialize some of the new
* cache's other internal fields. But don't open the relation yet.
* ----------------
*/
cp->cc_relname = relname;
@ -885,10 +885,20 @@ SearchCatCache(CatCache *cache,
RetrieveIndexResult indexRes;
HeapTupleData tuple;
Buffer buffer;
int i;
CACHE2_elog(DEBUG, "SearchCatCache(%s): performing index scan",
cache->cc_relname);
/*
* For an index scan, sk_attno has to be set to the index attribute
* number(s), not the heap attribute numbers. We assume that the
* index corresponds exactly to the cache keys (or its first N
* keys do, anyway).
*/
for (i = 0; i < cache->cc_nkeys; ++i)
cur_skey[i].sk_attno = i+1;
idesc = index_openr(cache->cc_indname);
isd = index_beginscan(idesc, false, cache->cc_nkeys, cur_skey);
tuple.t_datamcxt = CurrentMemoryContext;
@ -915,18 +925,10 @@ SearchCatCache(CatCache *cache,
else
{
HeapScanDesc sd;
int i;
CACHE2_elog(DEBUG, "SearchCatCache(%s): performing heap scan",
cache->cc_relname);
/*
* For a heap scan, sk_attno has to be set to the heap attribute
* number(s), not the index attribute numbers.
*/
for (i = 0; i < cache->cc_nkeys; ++i)
cur_skey[i].sk_attno = cache->cc_key[i];
sd = heap_beginscan(relation, 0, SnapshotNow,
cache->cc_nkeys, cur_skey);

4
src/include/utils/catcache.h
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@ -13,7 +13,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: catcache.h,v 1.28 2000/11/16 22:30:49 tgl Exp $
* $Id: catcache.h,v 1.29 2000/11/24 04:16:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -70,7 +70,7 @@ typedef struct catcache
short cc_nkeys; /* number of keys (1..4) */
short cc_key[4]; /* AttrNumber of each key */
PGFunction cc_hashfunc[4]; /* hash function to use for each key */
ScanKeyData cc_skey[4]; /* precomputed key info for indexscans */
ScanKeyData cc_skey[4]; /* precomputed key info for heap scans */
Dllist cc_lrulist; /* overall LRU list, most recent first */
Dllist cc_cache[NCCBUCK]; /* hash buckets */
} CatCache;