From: Heikki Linnakangas Date: Wed, 12 Dec 2012 11:34:03 +0000 (+0200) Subject: In multi-insert, don't go into infinite loop on a huge tuple and fillfactor. X-Git-Tag: REL9_3_BETA1~600 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6264cd3d69b519b6e6f2470e3c23ad1ef1ddff66;p=thirdparty%2Fpostgresql.git In multi-insert, don't go into infinite loop on a huge tuple and fillfactor. If a tuple is larger than page size minus space reserved for fillfactor, heap_multi_insert would never find a page that it fits in and repeatedly ask for a new page from RelationGetBufferForTuple. If a tuple is too large to fit on any page, taking fillfactor into account, RelationGetBufferForTuple will always expand the relation. In a normal insert, heap_insert will accept that and put the tuple on the new page. heap_multi_insert, however, does a fillfactor check of its own, and doesn't accept the newly-extended page RelationGetBufferForTuple returns, even though there is no other choice to make the tuple fit. Fix that by making the logic in heap_multi_insert more like the heap_insert logic. The first tuple is always put on the page RelationGetBufferForTuple gives us, and the fillfactor check is only applied to the subsequent tuples. Report from David Gould, although I didn't use his patch. --- diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 74c41fac3e9..e114d3dc45b 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -2185,8 +2185,12 @@ heap_multi_insert(Relation relation, HeapTuple *tuples, int ntuples, /* NO EREPORT(ERROR) from here till changes are logged */ START_CRIT_SECTION(); - /* Put as many tuples as fit on this page */ - for (nthispage = 0; ndone + nthispage < ntuples; nthispage++) + /* + * RelationGetBufferForTuple has ensured that the first tuple fits. + * Put that on the page, and then as many other tuples as fit. + */ + RelationPutHeapTuple(relation, buffer, heaptuples[ndone]); + for (nthispage = 1; ndone + nthispage < ntuples; nthispage++) { HeapTuple heaptup = heaptuples[ndone + nthispage];