Re: How to simulate crashes of PostgreSQL?

On Tue, Aug 25, 2009 at 4:55 PM, Tom Lane<tgl@sss.pgh.pa.us> wrote:
> I've always thought that the fd.c layer is more about not having to
> configure the code explicitly for max-files-per-process limits.  Once
> you get into ENFILE conditions, even if Postgres manages to stay up,
> everything else on the box is going to start falling over.  So the
> sysadmin is likely to have to resort to a reboot anyway.

In my case, all sorts of processes were complaining about being unable
to open files.  Once Pg panicked and closed all its files, everything
came back to normal.  I didn't have to reboot because most everything
was written to retry and/or restart itself, and nothing critical like
sshd croaked.

I think we'll be adding a nagios check to track maxfiles vs. openfiles
from the kernel and alarm when they get close.