pgsql: After PageSetAllVisible, use MarkBufferDirty.

After PageSetAllVisible, use MarkBufferDirty.

Previously, we used SetBufferCommitInfoNeedsSave, but that's really
intended for dirty-marks we can theoretically afford to lose, such as
hint bits.  As for 9.2, the PD_ALL_VISIBLE mustn't be lost in this
way, since we could then end up with a heap page that isn't
all-visible and a visibility map page that is all visible, causing
index-only scans to return wrong answers.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e93c0b820f03e96ae0549cd30805ae734e5d5e2f

Modified Files
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src/backend/commands/vacuumlazy.c |    4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)