Fetch XIDs atomically during vac_truncate_clog().
Because vac_update_datfrozenxid() updates datfrozenxid and datminmxid
in-place, it's unsafe to assume that successive reads of those values will
give consistent results. Fetch each one just once to ensure sane behavior
in the minimum calculation. Noted while reviewing Alexander Korotkov's
patch in the same area.
Discussion: <8564.1464116473@sss.pgh.pa.us>
Branch
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master
Details
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http://git.postgresql.org/pg/commitdiff/2d2e40e3befd8b9e0d2757554537345b15fa6ea2
Modified Files
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src/backend/commands/vacuum.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)