On Fri, 2007-10-26 at 14:39 -0700, David Rientjes wrote:
Maybe it's just me, but I think it's pretty presumptuous to think we can
infer the intent of the application from the nodemask w/o additional
flags such as Christoph proposed [cpuset relative]--especially for
subsets of the cpuset. E.g., the application could intend the nodemask
to specify memories within a certain distance of a physical resource,
such as where a particular IO adapter or set thereof attach to the
platform.
And even when the intent is to preserve the cpuset relative positions of
the nodes in the nodemask, this really only makes sense if the original
and modified cpusets have the same physical topology w/rt multi-level
NUMA interconnects. This is something that has bothered me about
dynamic cpusets and current policy remapping. We don't do a good job of
explaining the implications of changing cpuset topology on applications,
nor do we handle it very well in the code. Paul addresses one of my
concerns in a later message in this thread, so I'll comment there.
Later,
Lee
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