linux-kernel - decrease L2 cache size used by Linux?

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Message-Id: <200703170055.27126.a1426z@gawab.com>
Date:	Sat, 17 Mar 2007 00:55:27 +0300
From:	Al Boldi <a1426z@...ab.com>
To:	linux-kernel@...r.kernel.org
Subject: decrease L2 cache size used by Linux?

Guerreiro da Luz wrote:
> Am benchmarking dumb matrix multiplication in trying to perceive
> performance drop in case when matrix cannot fit in L2 cache.  However,
> on my machine L2 cache is large - 2MB, so 512x512 matrix of double
> numbers is needed to fill the cache, and in that case multiplication
> is taking rather long time.  So I'm wondering is there a way to
> control (decrease) L2 cache size used by Linux?  Apologies if question
> inappropriate for the list.

You may want to turn off randomization,
 
echo 0 > /proc/sys/kernel/randomize_va_space
echo 1 > /proc/sys/vm/vdso_enabled

And see if that helps.


Thanks!

--
Al

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