#endif
static void CatCacheRemoveCTup(CatCache *cache, CatCTup *ct);
static void CatCacheRemoveCList(CatCache *cache, CatCList *cl);
+static void RehashCatCache(CatCache *cp);
+static void RehashCatCacheLists(CatCache *cp);
static void CatalogCacheInitializeCache(CatCache *cache);
static CatCTup *CatalogCacheCreateEntry(CatCache *cache,
HeapTuple ntp, SysScanDesc scandesc,
long cc_neg_hits = 0;
long cc_newloads = 0;
long cc_invals = 0;
+ long cc_nlists = 0;
long cc_lsearches = 0;
long cc_lhits = 0;
if (cache->cc_ntup == 0 && cache->cc_searches == 0)
continue; /* don't print unused caches */
- elog(DEBUG2, "catcache %s/%u: %d tup, %ld srch, %ld+%ld=%ld hits, %ld+%ld=%ld loads, %ld invals, %ld lsrch, %ld lhits",
+ elog(DEBUG2, "catcache %s/%u: %d tup, %ld srch, %ld+%ld=%ld hits, %ld+%ld=%ld loads, %ld invals, %d lists, %ld lsrch, %ld lhits",
cache->cc_relname,
cache->cc_indexoid,
cache->cc_ntup,
cache->cc_searches - cache->cc_hits - cache->cc_neg_hits - cache->cc_newloads,
cache->cc_searches - cache->cc_hits - cache->cc_neg_hits,
cache->cc_invals,
+ cache->cc_nlist,
cache->cc_lsearches,
cache->cc_lhits);
cc_searches += cache->cc_searches;
cc_neg_hits += cache->cc_neg_hits;
cc_newloads += cache->cc_newloads;
cc_invals += cache->cc_invals;
+ cc_nlists += cache->cc_nlist;
cc_lsearches += cache->cc_lsearches;
cc_lhits += cache->cc_lhits;
}
- elog(DEBUG2, "catcache totals: %d tup, %ld srch, %ld+%ld=%ld hits, %ld+%ld=%ld loads, %ld invals, %ld lsrch, %ld lhits",
+ elog(DEBUG2, "catcache totals: %d tup, %ld srch, %ld+%ld=%ld hits, %ld+%ld=%ld loads, %ld invals, %ld lists, %ld lsrch, %ld lhits",
CacheHdr->ch_ntup,
cc_searches,
cc_hits,
cc_searches - cc_hits - cc_neg_hits - cc_newloads,
cc_searches - cc_hits - cc_neg_hits,
cc_invals,
+ cc_nlists,
cc_lsearches,
cc_lhits);
}
cache->cc_keyno, cl->keys);
pfree(cl);
+
+ --cache->cc_nlist;
}
* Invalidate *all* CatCLists in this cache; it's too hard to tell which
* searches might still be correct, so just zap 'em all.
*/
- dlist_foreach_modify(iter, &cache->cc_lists)
+ for (int i = 0; i < cache->cc_nlbuckets; i++)
{
- CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
+ dlist_head *bucket = &cache->cc_lbucket[i];
- if (cl->refcount > 0)
- cl->dead = true;
- else
- CatCacheRemoveCList(cache, cl);
+ dlist_foreach_modify(iter, bucket)
+ {
+ CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
+
+ if (cl->refcount > 0)
+ cl->dead = true;
+ else
+ CatCacheRemoveCList(cache, cl);
+ }
}
/*
int i;
/* Remove each list in this cache, or at least mark it dead */
- dlist_foreach_modify(iter, &cache->cc_lists)
+ for (i = 0; i < cache->cc_nlbuckets; i++)
{
- CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
+ dlist_head *bucket = &cache->cc_lbucket[i];
- if (cl->refcount > 0)
- cl->dead = true;
- else
- CatCacheRemoveCList(cache, cl);
+ dlist_foreach_modify(iter, bucket)
+ {
+ CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
+
+ if (cl->refcount > 0)
+ cl->dead = true;
+ else
+ CatCacheRemoveCList(cache, cl);
+ }
}
/* Remove each tuple in this cache, or at least mark it dead */
MCXT_ALLOC_ZERO);
cp->cc_bucket = palloc0(nbuckets * sizeof(dlist_head));
+ /*
+ * Many catcaches never receive any list searches. Therefore, we don't
+ * allocate the cc_lbuckets till we get a list search.
+ */
+ cp->cc_lbucket = NULL;
+
/*
* initialize the cache's relation information for the relation
* corresponding to this cache, and initialize some of the new cache's
cp->cc_relisshared = false; /* temporary */
cp->cc_tupdesc = (TupleDesc) NULL;
cp->cc_ntup = 0;
+ cp->cc_nlist = 0;
cp->cc_nbuckets = nbuckets;
+ cp->cc_nlbuckets = 0;
cp->cc_nkeys = nkeys;
for (i = 0; i < nkeys; ++i)
cp->cc_keyno[i] = key[i];
cp->cc_bucket = newbucket;
}
+/*
+ * Enlarge a catcache's list storage, doubling the number of buckets.
+ */
+static void
+RehashCatCacheLists(CatCache *cp)
+{
+ dlist_head *newbucket;
+ int newnbuckets;
+ int i;
+
+ elog(DEBUG1, "rehashing catalog cache id %d for %s; %d lists, %d buckets",
+ cp->id, cp->cc_relname, cp->cc_nlist, cp->cc_nlbuckets);
+
+ /* Allocate a new, larger, hash table. */
+ newnbuckets = cp->cc_nlbuckets * 2;
+ newbucket = (dlist_head *) MemoryContextAllocZero(CacheMemoryContext, newnbuckets * sizeof(dlist_head));
+
+ /* Move all entries from old hash table to new. */
+ for (i = 0; i < cp->cc_nlbuckets; i++)
+ {
+ dlist_mutable_iter iter;
+
+ dlist_foreach_modify(iter, &cp->cc_lbucket[i])
+ {
+ CatCList *cl = dlist_container(CatCList, cache_elem, iter.cur);
+ int hashIndex = HASH_INDEX(cl->hash_value, newnbuckets);
+
+ dlist_delete(iter.cur);
+ dlist_push_head(&newbucket[hashIndex], &cl->cache_elem);
+ }
+ }
+
+ /* Switch to the new array. */
+ pfree(cp->cc_lbucket);
+ cp->cc_nlbuckets = newnbuckets;
+ cp->cc_lbucket = newbucket;
+}
+
/*
* CatalogCacheInitializeCache
*
Datum v4 = 0; /* dummy last-column value */
Datum arguments[CATCACHE_MAXKEYS];
uint32 lHashValue;
+ Index lHashIndex;
dlist_iter iter;
+ dlist_head *lbucket;
CatCList *cl;
CatCTup *ct;
List *volatile ctlist;
/*
* one-time startup overhead for each cache
*/
- if (cache->cc_tupdesc == NULL)
+ if (unlikely(cache->cc_tupdesc == NULL))
CatalogCacheInitializeCache(cache);
Assert(nkeys > 0 && nkeys < cache->cc_nkeys);
arguments[3] = v4;
/*
- * compute a hash value of the given keys for faster search. We don't
- * presently divide the CatCList items into buckets, but this still lets
- * us skip non-matching items quickly most of the time.
+ * If we haven't previously done a list search in this cache, create the
+ * bucket header array; otherwise, consider whether it's time to enlarge
+ * it.
+ */
+ if (cache->cc_lbucket == NULL)
+ {
+ /* Arbitrary initial size --- must be a power of 2 */
+ int nbuckets = 16;
+
+ cache->cc_lbucket = (dlist_head *)
+ MemoryContextAllocZero(CacheMemoryContext,
+ nbuckets * sizeof(dlist_head));
+ /* Don't set cc_nlbuckets if we get OOM allocating cc_lbucket */
+ cache->cc_nlbuckets = nbuckets;
+ }
+ else
+ {
+ /*
+ * If the hash table has become too full, enlarge the buckets array.
+ * Quite arbitrarily, we enlarge when fill factor > 2.
+ */
+ if (cache->cc_nlist > cache->cc_nlbuckets * 2)
+ RehashCatCacheLists(cache);
+ }
+
+ /*
+ * Find the hash bucket in which to look for the CatCList.
*/
lHashValue = CatalogCacheComputeHashValue(cache, nkeys, v1, v2, v3, v4);
+ lHashIndex = HASH_INDEX(lHashValue, cache->cc_nlbuckets);
/*
* scan the items until we find a match or exhaust our list
* Note: it's okay to use dlist_foreach here, even though we modify the
* dlist within the loop, because we don't continue the loop afterwards.
*/
- dlist_foreach(iter, &cache->cc_lists)
+ lbucket = &cache->cc_lbucket[lHashIndex];
+ dlist_foreach(iter, lbucket)
{
cl = dlist_container(CatCList, cache_elem, iter.cur);
continue;
/*
- * We found a matching list. Move the list to the front of the
- * cache's list-of-lists, to speed subsequent searches. (We do not
+ * We found a matching list. Move the list to the front of the list
+ * for its hashbucket, so as to speed subsequent searches. (We do not
* move the members to the fronts of their hashbucket lists, however,
* since there's no point in that unless they are searched for
* individually.)
*/
- dlist_move_head(&cache->cc_lists, &cl->cache_elem);
+ dlist_move_head(lbucket, &cl->cache_elem);
/* Bump the list's refcount and return it */
ResourceOwnerEnlargeCatCacheListRefs(CurrentResourceOwner);
}
Assert(i == nmembers);
- dlist_push_head(&cache->cc_lists, &cl->cache_elem);
+ /*
+ * Add the CatCList to the appropriate bucket, and count it.
+ */
+ dlist_push_head(lbucket, &cl->cache_elem);
+
+ cache->cc_nlist++;
/* Finally, bump the list's refcount and return it */
cl->refcount++;
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