Reset pg_stat_activity.xact_start during PREPARE TRANSACTION.
Once we've completed a PREPARE, our session is not running a transaction,
so its entry in pg_stat_activity should show xact_start as null, rather
than leaving the value as the start time of the now-prepared transaction.
I think possibly this oversight was triggered by faulty extrapolation
from the adjacent comment that says PrepareTransaction should not call
AtEOXact_PgStat, so tweak the wording of that comment.
Noted by Andres Freund while considering bug #10123 from Maxim Boguk,
although this error doesn't seem to explain that report.
Back-patch to all active branches.
Branch
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REL9_2_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/ea9ac774198ad097d2d322f81c39bd8cdfa8b04d
Modified Files
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src/backend/access/transam/xact.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)