Re: [PATCH 1/5] cpuset memory spread basic implementation

[Paul Jackson <pj@sgi.com>]

Ingo asked:
> so in practice, the memory spreading is in fact a global setting, used
> by all cpusets that matter? 

I don't know if that is true or not.

I'll have to ask my field engineers, who actually have experience
with a variety of customer workloads.

... well, I do have partial knowledge of this.

When I was coding this, I suggested that instead of picking some of the
slab caches to memory spread, we pick them all, as that would be easier
to code.

That suggestion was shot down by others more experienced within SGI, as
some slab caches hold what is essentially per-thread data, that is
fairly hot in the thread context that allocated it.  Spreading that data
would quite predictably increase cross-node bus traffic, which is bad.

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj@sgi.com> 1.925.600.0401
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