Hello KaiGai-san,
I've discovered a bug in the proposed patch - when resetting the hash
table after the first batch, it does this:
memset(hashtable->buckets, 0, sizeof(nbuckets * sizeof(HashJoinTuple)));
The first 'sizeof' is bogus, so this only zeroes the first 8 bytes of
the array (usually resulting in crashes due to invalid pointers).
I fixed it to
memset(hashtable->buckets, 0, nbuckets * sizeof(HashJoinTuple));
Fixed patch attached (marked as v2).
kind regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
src/backend/executor/nodeHash.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/src/backend/executor/nodeHash.c b/src/backend/executor/nodeHash.c
index 906cb46..63d484c 100644
--- a/src/backend/executor/nodeHash.c
+++ b/src/backend/executor/nodeHash.c
@@ -388,7 +388,9 @@ ExecHashTableCreate(Hash *node, List *hashOperators, bool keepNulls)
MemoryContextSwitchTo(hashtable->batchCxt);
hashtable->buckets = (HashJoinTuple *)
- palloc0(nbuckets * sizeof(HashJoinTuple));
+ MemoryContextAllocHuge(hashtable->batchCxt,
+ nbuckets * sizeof(HashJoinTuple));
+ memset(hashtable->buckets, 0, nbuckets * sizeof(HashJoinTuple));
/*
* Set up for skew optimization, if possible and there's a need for more
@@ -654,7 +656,7 @@ ExecHashIncreaseNumBatches(HashJoinTable hashtable)
hashtable->nbuckets = hashtable->nbuckets_optimal;
hashtable->log2_nbuckets = hashtable->log2_nbuckets_optimal;
- hashtable->buckets = repalloc(hashtable->buckets,
+ hashtable->buckets = repalloc_huge(hashtable->buckets,
sizeof(HashJoinTuple) * hashtable->nbuckets);
}
@@ -779,7 +781,7 @@ ExecHashIncreaseNumBuckets(HashJoinTable hashtable)
* chunks)
*/
hashtable->buckets =
- (HashJoinTuple *) repalloc(hashtable->buckets,
+ (HashJoinTuple *) repalloc_huge(hashtable->buckets,
hashtable->nbuckets * sizeof(HashJoinTuple));
memset(hashtable->buckets, 0, sizeof(void *) * hashtable->nbuckets);
@@ -1217,7 +1219,9 @@ ExecHashTableReset(HashJoinTable hashtable)
/* Reallocate and reinitialize the hash bucket headers. */
hashtable->buckets = (HashJoinTuple *)
- palloc0(nbuckets * sizeof(HashJoinTuple));
+ MemoryContextAllocHuge(hashtable->batchCxt,
+ nbuckets * sizeof(HashJoinTuple));
+ memset(hashtable->buckets, 0, nbuckets * sizeof(HashJoinTuple));
hashtable->spaceUsed = 0;
--
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