zh1029 <zh1029(at)sina(dot)com> writes:
> Unfortunately what's the process 2720 is unknown as no any else log to
> indicate it. It might because the debug level of PostgreSQL had been set too
> lower to show more.
The query you quoted for 2720 looks exactly like one that pg_dump will
issue, cf dumpSequence(). What I think is going on here is that you've
got some cron job that aggressively connects to the database and runs a
pg_dump the moment you start it. It's unsurprising that that would
deadlock against a pg_restore -C.
regards, tom lane