On 2013-05-17, Loïc BLOT <loic.blot_at_unix-experience.fr> wrote:
> I have found the problem. In fact it's the problem mentionned on my last
> mail, is right. Squid FD limit was reached, but squid doesn't mentionned
> every time the freeze appear that it's a FD limit problem, then the
> debug was so difficult.
> Also, i think you must add a non portable check to check if squid FD
> limit isn't greater than system ulimit (ulimit -n under OpenBSD). Squid
> doesn't mention that and when this appear, it's also a freeze (squid FD
> saturation) and no warning is mentionned in the logs. This check would
> be at the squid start/reload.
>
> What do you think about it ?
Checking (e.g. via getrlimit) to see if the limit is too small is the
wrong approach. System calls needing FDs can fail if *either* the current
process hits its limits, *or* if the system file table is full.
Various software in OpenBSD has been audited for problems in this
area fairly recently, here are a few of the commits which resulted
showing examples of various approaches we used,
nginx: http://anoncvs.estpak.ee/cgi-bin/cgit/openbsd-src/commit/?id=c2d55a68002aae78bcd8ba0198f0a2d3f92cd777
tmux: http://anoncvs.estpak.ee/cgi-bin/cgit/openbsd-src/commit/?id=a5b691fe6fa8b648e7d7465167a96f667e40295c
unbound: http://anoncvs.estpak.ee/cgi-bin/cgit/openbsd-src/commit/?id=b9781e8c60007fbc60cf8a5509154b0283874682
openbgp: http://anoncvs.estpak.ee/cgi-bin/cgit/openbsd-src/commit/?id=bee609c47fa933f06b924435e7f41c661a8a3b40
identd: http://anoncvs.estpak.ee/cgi-bin/cgit/openbsd-src/commit/?id=9ca56282c96c6482f23cbd459d2ab9d0cc55a68e
cheers,
Stuart
Received on Fri May 17 2013 - 20:50:08 MDT
This archive was generated by hypermail 2.2.0 : Sat May 18 2013 - 12:00:17 MDT