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Subject: Re: [hwloc-devel] hwloc_alloc_membind
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2012-02-24 07:52:19

Karl Napf, le Fri 24 Feb 2012 13:04:58 +0100, a écrit :
> What surprises me is that the result of the call to
> hwloc_fix_membind_cpuset in line 534 of bind.c is negated, even though
> hwloc_fix_membind_cpuset returns 0 on success. Might this be a bug?

Oops, indeed.

> 2. In another use case I want to allocate memory using the first-touch
> policy (HWLOC_MEMBIND_FIRSTTOUCH). Does the cpuset passed to
> hwloc_alloc_membind have any meaning in this case, since the memory is
> not immediately bound to a node?

It has a meaning when there is not enough memory on the node. Allocation
may then be done in some node of the given cpuset. This kind of precise
detail on the behavior however vary over OSes. Linux does not take it
into account for instance.