nginx-1.3.14: alert sched_setaffinity() failed

[Maxim Dounin]

Hello!

On Tue, Mar 05, 2013 at 07:38:30PM +0100, Patrick Lists wrote:

> Hi,
> 
> On an updated CentOS 6.3 x86_64 VM I just installed nginx 1.3.14
> with extra modules ngx_cache_purge and nginx-auth-ldap, the SPDY 66
> patch and built statically against openssl-1.0.1e. In the error log
> I see this message:
> 
> 2013/03/05 19:31:39 [alert] 13363#0: sched_setaffinity() failed (22:
> Invalid argument)
> 
> No idea what it means. Maybe it is helpful for the developers.

Do you have worker_cpu_affinity (http://nginx.org/r/worker_cpu_affinity) 
in your config?  Does it match CPUs available?

The message indicate that from kernel point of view configured CPU 
mask is wrong:

       EINVAL The affinity bit mask mask contains no processors that  are
              currently  physically  on  the  system and permitted to the
              process according to any restrictions that may  be  imposed
              by the "cpuset" mechanism described in cpuset(7).

An easy way to trigger the message above is to do something like

    worker_cpu_affinity  10;

on a system with one CPU only.

-- 
Maxim Dounin
http://nginx.org/en/donation.html