From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Date: Tue, 07 Feb 2006 02:56:04 +0000
Subject: RE: [patch 3/6] prefetch bottom of kernel rbs stack at syscall exit path
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To: linux-ia64@vger.kernel.org

Chen, Kenneth wrote on Tuesday, January 31, 2006 11:27 AM
> David Mosberger-Tang wrote on Tuesday, January 31, 2006 9:45 AM
> > How much latency does this add for a minimal syscall when
> > everything is cached?
> 
> I will get the measurement out shortly.

Here are the numbers for break based getpid():

Vanilla 2.6.15:    238 cycles
Vanilla + patches: 250 cycles

- Ken