Tom Lane wrote:
> That seems like (a) a hack, and (b) not likely to solve the problem
> completely, unless you leave interrupts held throughout proc_exit(),
> which would create all sorts of opportunities for corner case bugs
> during on_proc_exit hooks.
>
> I think changing the outer "for(;;)" to "while (!got_SIGTERM)" would
> be a much safer fix.
Ah, yeah. I was thinking in changing PG_exception_stack once shutdown
was requested, but this is much simpler.
> It looks like there's a related risk associated with this bit:
>
> /* in emergency mode, just start a worker and go away */
> if (!AutoVacuumingActive())
> {
> do_start_worker();
> proc_exit(0); /* done */
> }
>
> If we get SIGHUP and see that autovacuum has been turned off,
> we exit the main loop, but we don't set got_SIGTERM. So if we
> then get a similar error at the shutdown report, we'd not merely
> waste some time, but actually incorrectly launch a child.
Well, what it does is request a new child from postmaster, which
presumably wouldn't be listening; but yeah there's a lot of other work
done here also.
How about the attached?
--
Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
