On Fri, Jan 14, 2011 at 2:01 PM, Kevin Grittner
<Kevin.Grittner@wicourts.gov> wrote:
>> Trouble is, it breaks Hot Standby, badly.
>
> You're really starting to worry me here. Both for performance and
> to reduce the WAN bandwidth demands of our backup strategy we are
> very aggressive with our freezing. Do off-hours VACUUM (FREEZE)
> runs break hot standby? Autovacuum freezing? What are the
> symptoms?
Freezing removes XIDs, so latestRemovedXid advances. VACUUM (FREEZE)
is fine if you do it when there are no queries running on your Hot
Standby server, but if there ARE queries running on the Hot Standby
server, they'll be cancelled once max_standby_delay expires.
--
Robert Haas
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