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Subject: Re: [hwloc-devel] 1.0.3rc3 and 1.1rc5
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2010-12-20 14:22:38


Le 20/12/2010 20:06, Guy Streeter a écrit :
> I decided I should just give you the whole output.

Thanks. Indeed, it's a Linux "feature". When you request a non-strict
memory binding in Linux (MPOL_PREFERRED, not MPOL_BIND), it only keeps
the first node in the input nodemask. Instead of allocating on X,Y,Z
when possible and anywhere else otherwise, it allocates on X when
possible and anywhere else otherwise.

That's why we get 0x0000003f (first node cpuset) instead of 0x00ffffff
(four first nodes cpuset) when we request the current binding.

Brice