Re: thread_create() failed

From: Murray S. Kucherawy <msk_at_blackops.org>
Date: Thu, 28 Jun 2012 07:23:30 -0700 (PDT)

On Thu, 28 Jun 2012, Andreas Schulze wrote:
> Jun 28 01:19:21 mailin11 opendkim[3987]: OpenDKIM Filter: thread_create() failed: 12, try again
>
> [...]
>
> Sometimes it worked, most times not.
> Clients got tempfails from the MTA.
> Restarting OpenDKIM solved the problem.
> OS: Linux-2.6.5
>[...]
>
> How could I monitor why thread_create failed?

The error code of 12 is ENOMEM. A new connection arrived and libmilter
couldn't allocate another thread.

The cause of this could be anything from high load to a deadlock. When
you see it happening, try to get a core dump (see the "gcore" man page)
and then use gdb to get a stack trace from it from all threads ("thread
apply all where"). The output can be quite long, but it's useful to
determine whether the cause was a bug or overload.

-MSK
Received on Thu Jun 28 2012 - 14:24:07 PST