On Fri, Nov 4, 2011 at 10:34 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert's point about sinval catchup is another good one, though
> I don't remember what that does to the pg_stat_activity display.
My thought was that sinval catchup might require acquiring a relation
lock (e.g. on pg_class), and that might block waiting for a lock.
Not sure it's possible, but even if it can't happen today, it doesn't
seem impossible that we might want to let it happen in the future.
--
Robert Haas
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