Measuring page faults

From: Mike Gagnon
Date: Fri Nov 20 2009 - 09:06:40 EST


Hi all,

I would like to measure the latency (execution time) of Linux page
faults.  I tried using lmbench, but I get unrealistically fast results
from the lmbench lat_pagefault benchmark.  The problem seems to be
that lmbench attempts to ensure pages are paged out using msync with
the MS_INVALIDATE flag set, but this doesn't seem to cause page outs
on Linux.  http://www.bitmover.com/lmbench/lat_pagefault.8.html

I would like to adapt lmbench to correctly measure page faults on
Linux, but I need a mechanism to ensure specific pages are paged-out.
Is there a good way to reliably cause page-outs in Linux (so that I
may then cause page faults by touching the paged-out pages)?

Thanks,
Michael Gagnon
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