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Subject: Re: [hwloc-users] hwloc_get_last_cpu_location and hwloc_get_cpubind
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2012-01-17 05:59:59


Marc-André Hermanns, le Tue 17 Jan 2012 11:47:43 +0100, a écrit :
> It seems now that it has the whole system in the cpuset. How can I
> really infer the PU this process was run on? I would have expected the
> cpuset to have only 1 element per level to indicate the path from
> machine to PU.

That is what is expected, yes (though only at the PU level, since
only that one is completely included in the cpuset, you would need
"intersects" to get the path). and that's what I get on my machine:

¤ ./test
This system has 7 levels
Cpuset: 0x00000040
Number of objects at depth 0: 0
Number of objects at depth 1: 0
Number of objects at depth 2: 0
Number of objects at depth 3: 0
Number of objects at depth 4: 0
Number of objects at depth 5: 0
Number of objects at depth 6: 1

> Evidently my understanding of this functionality is still
> not correct.

No, it's completely correct, it just seems there's an odd thing
somewhere. Could you run through strace so we can check what the kernel
returns?

Samuel