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Message-ID: <3FA8ECF0.8020800@cyberone.com.au>
Date: Wed, 05 Nov 2003 23:28:32 +1100
From: Nick Piggin <piggin@cyberone.com.au>
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To: Linus Torvalds <torvalds@osdl.org>, Andrew Morton <akpm@osdl.org>
CC: linux-kernel <linux-kernel@vger.kernel.org>
Subject: lmbench context switch regression
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Hi,
I'm seeing quite a large context switch speed regression as reported
by lmbench when I patched from test9 to test9-mm2.

The obvious thing I can see from the patch is the PF_DEAD finish_task_switch
change. I don't have time to investigate further tonight though.

lmbench two 0 sized processes context switch times go from around 1.80us to
2.60us on my PIII 650 (UP).