Message-ID: <20040310111919.83754.qmail@web10901.mail.yahoo.com>
Date: Wed, 10 Mar 2004 03:19:19 -0800 (PST)
From: Ashwin Rao <ashwin_s_rao@yahoo.com>
Subject: inconsistent do_gettimeofday for copy_page
To: linux-kernel@vger.kernel.org, linux-mm@kvack.org
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For calculating the time required to copy_page i tried
the do_gettimeofday for 1000 pages in a loop. But as
the number of pages changes the time required varies
non-linearly.
I also tried reading xtime and using monotonic_clock
but they didnt help either. For do_gettimeof day for a
single invocation of copy_page on a pentium 4 gave me
10 microsecs but when invoked for a 1000 pages the
time required was 750ns per page.
Is there some way of finding out the exact time
required for copying a page.

Ashwin

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