At Thu, 28 Jan 2021 16:50:44 +0900 (JST), Kyotaro Horiguchi
<horikyota....@gmail.com> wrote in
> I was going to write in the doc something like "you can inspect memory
> consumption by catalog caches using pg_backend_memory_contexts", but
> all the memory used by catalog cache is in CacheMemoryContext. Is it
> sensible for each catalog cache to have their own contexts?
Something like this.
regards.
--
Kyotaro Horiguchi
NTT Open Source Software Center
diff --git a/src/backend/utils/cache/catcache.c
b/src/backend/utils/cache/catcache.c
index fa2b49c676..cfbb335bb3 100644
--- a/src/backend/utils/cache/catcache.c
+++ b/src/backend/utils/cache/catcache.c
@@ -769,6 +769,8 @@ InitCatCache(int id,
{
CatCache *cp;
MemoryContext oldcxt;
+ MemoryContext mycxt;
+ char name[32];
size_t sz;
int i;
@@ -792,7 +794,12 @@ InitCatCache(int id,
if (!CacheMemoryContext)
CreateCacheMemoryContext();
- oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+ mycxt = AllocSetContextCreate(CacheMemoryContext, "catcache",
+
ALLOCSET_DEFAULT_SIZES);
+
+ snprintf(name, sizeof(name), "catcache id %d", id);
+ oldcxt = MemoryContextSwitchTo(mycxt);
+ MemoryContextSetIdentifier(mycxt, (const char *)pstrdup(name));
/*
* if first time through, initialize the cache group header
@@ -833,6 +840,7 @@ InitCatCache(int id,
cp->cc_nkeys = nkeys;
for (i = 0; i < nkeys; ++i)
cp->cc_keyno[i] = key[i];
+ cp->cc_mcxt = mycxt;
/*
* new cache is initialized as far as we can go for now. print some
@@ -932,12 +940,12 @@ CatalogCacheInitializeCache(CatCache *cache)
relation = table_open(cache->cc_reloid, AccessShareLock);
/*
- * switch to the cache context so our allocations do not vanish at the
end
- * of a transaction
+ * switch to our own context under the cache context so our allocations
do
+ * not vanish at the end of a transaction
*/
Assert(CacheMemoryContext != NULL);
- oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+ oldcxt = MemoryContextSwitchTo(cache->cc_mcxt);
/*
* copy the relcache's tuple descriptor to permanent cache storage
@@ -998,7 +1006,7 @@ CatalogCacheInitializeCache(CatCache *cache)
*/
fmgr_info_cxt(eqfunc,
&cache->cc_skey[i].sk_func,
- CacheMemoryContext);
+ cache->cc_mcxt);
/* Initialize sk_attno suitably for HeapKeyTest() and heap
scans */
cache->cc_skey[i].sk_attno = cache->cc_keyno[i];
@@ -1697,7 +1705,7 @@ SearchCatCacheList(CatCache *cache,
table_close(relation, AccessShareLock);
/* Now we can build the CatCList entry. */
- oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+ oldcxt = MemoryContextSwitchTo(cache->cc_mcxt);
nmembers = list_length(ctlist);
cl = (CatCList *)
palloc(offsetof(CatCList, members) + nmembers *
sizeof(CatCTup *));
@@ -1830,7 +1838,7 @@ CatalogCacheCreateEntry(CatCache *cache, HeapTuple ntp,
Datum *arguments,
dtp = ntp;
/* Allocate memory for CatCTup and the cached tuple in one go */
- oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+ oldcxt = MemoryContextSwitchTo(cache->cc_mcxt);
ct = (CatCTup *) palloc(sizeof(CatCTup) +
MAXIMUM_ALIGNOF
+ dtp->t_len);
@@ -1865,7 +1873,7 @@ CatalogCacheCreateEntry(CatCache *cache, HeapTuple ntp,
Datum *arguments,
else
{
Assert(negative);
- oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+ oldcxt = MemoryContextSwitchTo(cache->cc_mcxt);
ct = (CatCTup *) palloc(sizeof(CatCTup));
/*
diff --git a/src/include/utils/catcache.h b/src/include/utils/catcache.h
index ddc2762eb3..a32fea2f11 100644
--- a/src/include/utils/catcache.h
+++ b/src/include/utils/catcache.h
@@ -61,6 +61,7 @@ typedef struct catcache
slist_node cc_next; /* list link */
ScanKeyData cc_skey[CATCACHE_MAXKEYS]; /* precomputed key info for heap
* scans */
+ MemoryContext cc_mcxt; /* memory context for this cache */
/*
* Keep these at the end, so that compiling catcache.c with
CATCACHE_STATS
