pgsql: In multi-insert, don't go into infinite loop on a huge tuple and - Mailing list pgsql-committers

From Heikki Linnakangas
Subject pgsql: In multi-insert, don't go into infinite loop on a huge tuple and
Date
Msg-id E1TikuT-0007Zl-29@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
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.

Branch
------
REL9_2_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/77a1ba20aa7b7caae4396e2afa5d86132fd36f6b

Modified Files
--------------
src/backend/access/heap/heapam.c |    8 ++++++--
1 files changed, 6 insertions(+), 2 deletions(-)


pgsql-committers by date:

Previous
From: Tom Lane
Date:
Subject: pgsql: Add defenses against integer overflow in dynahash numbuckets cal
Next
From: Heikki Linnakangas
Date:
Subject: pgsql: Make xlog_internal.h includable in frontend context.