Re: Streaming replica hangs periodically for ~ 1 second - how to diagnose/debug

hubert depesz lubaczewski <depesz@depesz.com> writes:
> I got repeatable case today. Is is breaking on its own everyy
> ~ 5 minutes.

Interesting.  That futex call is presumably caused by interaction
with some other process within the standby server, and the only
plausible candidate really is the startup process (which is replaying
WAL received from the primary).  There are cases where WAL replay
will take locks that can block queries on the standby.  Can you
correlate the delays on the standby server with any DDL events
occurring on the primary?

			regards, tom lane