pgsql: XidEpoch++ if wraparound during checkpoint. - Mailing list pgsql-committers

From Simon Riggs
Subject pgsql: XidEpoch++ if wraparound during checkpoint.
Date
Msg-id E1TfB4O-0008EH-Ll@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
XidEpoch++ if wraparound during checkpoint.
If wal_level = hot_standby we update the checkpoint nextxid,
though in the case where a wraparound occurred half-way through
a checkpoint we would neglect updating the epoch also. Updating
the nextxid is arguably the wrong thing to do, but changing that
may introduce subtle bugs into hot standby startup, while updating
the value doesn't cause any known bugs yet. Minimal fix now to
HEAD and backbranches, wider fix later in HEAD.

Bug reported in #6291 by Daniel Farina and slightly differently in

Cause analysis and recommended fixes from Tom Lane and Andres Freund.

Applied patch is minimal version of Andres Freund's work.

Branch
------
REL9_2_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/c3f64adef829ea41d3761822b8a043aec3d651f2

Modified Files
--------------
src/backend/access/transam/xlog.c |    9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)


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