Don't try to set InvalidXid as page pruning hint
If a transaction updates/deletes a tuple just before aborting, and a
concurrent transaction tries to prune the page concurrently, the pruner
may see HeapTupleSatisfiesVacuum return HEAPTUPLE_DELETE_IN_PROGRESS,
but a later call to HeapTupleGetUpdateXid() return InvalidXid. This
would cause an assertion failure in development builds, but would be
otherwise Mostly Harmless.
Fix by checking whether the updater Xid is valid before trying to apply
it as page prune point.
Reported by Andres in 20131124000203.GA4403@alap2.anarazel.de
Branch
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master
Details
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http://git.postgresql.org/pg/commitdiff/c235a6a589bbd0a24e54fdb0df28979c9fb09463
Modified Files
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src/backend/access/heap/pruneheap.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)