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Subject: Re: [hwloc-devel] Crash with ignoring HWLOC_OBJ_NODE in 0.9.2
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2009-11-20 09:54:43


Hello,

Michael Raymond, le Fri 20 Nov 2009 08:43:10 -0600, a écrit :
> In one pattern I might want to place processes on all the Cores in a
> Misc and then move to the next Misc. A topology tree that looks like
> System -> Misc -> Core makes that easy. Having Nodes in there just adds
> unneeded complexity.

Ok, I see. What I'd see is instead of using the MISC type for numa
groups, introducing a NUMAGROUP object type. In that case, ignoring
NUMA but not NUMAGROUP makes sense and would provide that result.

However, with a better version of hwloc you may still get

System -> Numagroup -> Numagroup -> Core

because e.g. thanks to more precise distances hwloc has noticed that the
first Numagroup level itself is hierarchical, forming another Numagroup
level.

Introduce several numagroup types? How many? That's not easy to
answer.

Samuel