Обсуждение: pgsql: Fix bug in early startup of Hot Standby with subtransactions.

Fix bug in early startup of Hot Standby with subtransactions.
When HS startup is deferred because of overflowed subtransactions, ensure
that we re-initialize KnownAssignedXids for when both existing and incoming
snapshots have non-zero qualifying xids.

Fixes bug #6661 reported by Valentine Gogichashvili.

Analysis and fix by Andres Freund

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/557433f48ad1e55ce753282f4dfb8ef3606cda8d

Modified Files
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src/backend/storage/ipc/procarray.c |   32 +++++++++++++++++++++++++++++++-
1 files changed, 31 insertions(+), 1 deletions(-)