Open MPI logo

Hardware Locality Users' Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Hardware Locality Users mailing list

Subject: Re: [hwloc-users] Process and thread binding
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2011-09-12 07:38:05

Le 12/09/2011 13:29, Gabriele Fatigati a écrit :
> Hi Birce,
> I'm so confused..
> I'm binding MPI processes with set_cpu_bind and it works well. The
> problem is when I try to bind process and threads.
> It seem that thread process influence bind of main thread.
> And from hwloc manual:
> hwloc_set_cpubind()
> Bind *current process* or thread on cpus given in bitmap set.
> Why you are saying tha process bind is not possible? I'm using it and
> it work well!

It worked because you never mixed it with single thread binding. If you
bind process X to coreA and then thread Y of process X to coreB, what
you should now see with get_cpubind is that process X is now bound to
cores A+B, thread Y to B, and all other threads to A.