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Subject: Re: [hwloc-users] Process and thread binding
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2011-09-12 07:17:54


Le 12/09/2011 12:52, Gabriele Fatigati a écrit :
> Dear hwloc users,
>
> I'm binding process in a NUMA node and also associated OpenMP threads.
> I've noted that, if I bind execution of all on different cores in
> the same NUMA node , it works well.
>
> If I bind process in NUMA node 0 for example, and thread on NUMA node
> 1, the process is bound on NUMA node 1, and not 0.
>
> Why this? Thread binding influence bind of main process?
>

Hello Gabriele,
At least on Linux, you cannot bind a process. When you ask hwloc to bind
a process, it just binds all threads contained in this process. When you
do get_cpubind on a process, it returns the logical OR of the binding of
all threads.
Brice