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Date: Wed, 20 Dec 2017 09:58:30 -0600 (CST)
From: Christopher Lameter <cl@linux.com>
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To: kemi <kemi.wang@intel.com>
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Subject: Re: [PATCH v2 4/5] mm: use node_page_state_snapshot to avoid
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On Wed, 20 Dec 2017, kemi wrote:

> > You are making numastats special and I yet haven't heard any sounds
> > arguments for that. But that should be discussed in the respective
> > patch.
> >
>
> That is because we have much larger threshold size for NUMA counters, that means larger
> deviation. So, the number in local cpus may not be simply ignored.

Some numbers showing the effect of these changes would be helpful. You can
probably create some in kernel synthetic tests to start with which would
allow you to see any significant effects of those changes.

Then run the larger testsuites (f.e. those that Mel has published) and
benchmarks to figure out how behavior of real apps *may* change?