Re: Return of the Solaris vacuum polling problem -- anyone remember this?

Excerpts from Joe Conway's message of lun ago 16 16:47:19 -0400 2010:
> On 08/16/2010 12:12 PM, Josh Berkus wrote:
> >
> >> I've also recently heard a report of vacuum hanging on 8.3.x on Solaris
> >> Sparc. Any chance you can get a backtrace from a build with debug symbols?
> >
> > The problem is that we haven't been able to reproduce the bug in
> > testing. Like I said, it only seems to happen occasionally ... like
> > maybe once in 10 or 20 (or more?) autovacuums. We've never been seen it
> > with a manual vacuum at all.
> >
> > And we can't rebuild the production servers.
>
> Hmmm, well I don't know how to reproduce it on demand either -- I'll try
> to get a backtrace from the wild if possible. I'll keep you posted...

FWIW there's also a report of it hanging in FreeBSD, but sadly when the
process is inspected under truss, it dies because of its "parent PID"
attribute changing underneath and thus triggering the safety feature
that makes it die if the parent postmaster disappears.

I suspect that the problem may lie in the "cost_delay rebalance" code in
autovacuum.

--
Álvaro Herrera <alvherre(at)commandprompt(dot)com>
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