From 8c0c25fc894de49054fb6711af96cbcf61cc2b51 Mon Sep 17 00:00:00 2001 From: Tomas Vondra Date: Wed, 30 Dec 2015 14:02:26 +0100 Subject: [PATCH 2/5] always start in un-batched mode --- src/backend/executor/nodeHash.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/src/backend/executor/nodeHash.c b/src/backend/executor/nodeHash.c index 7708581..e7d4b5f 100644 --- a/src/backend/executor/nodeHash.c +++ b/src/backend/executor/nodeHash.c @@ -290,7 +290,7 @@ ExecHashTableCreate(Hash *node, List *hashOperators, bool keepNulls) hashtable->skewBucketLen = 0; hashtable->nSkewBuckets = 0; hashtable->skewBucketNums = NULL; - hashtable->nbatch = nbatch; + hashtable->nbatch = 1; hashtable->curbatch = 0; hashtable->nbatch_original = nbatch; hashtable->nbatch_outstart = nbatch; @@ -600,7 +600,15 @@ ExecHashIncreaseNumBatches(HashJoinTable hashtable) if (oldnbatch > Min(INT_MAX / 2, MaxAllocSize / (sizeof(void *) * 2))) return; - nbatch = oldnbatch * 2; + /* + * If we're incrementing the number of batches for the first time, + * let's see if we should start with nbatch_original. + */ + if ((oldnbatch == 1) && (hashtable->nbatch_original > 1)) + nbatch = hashtable->nbatch_original; + else + nbatch = oldnbatch * 2; + Assert(nbatch > 1); #ifdef HJDEBUG -- 2.1.0