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Date: Tue, 16 Apr 2002 18:02:17 -0700 (PDT)
From: Davide Libenzi <davidel@xmailserver.org>
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To: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
cc: davidm@hpl.hp.com, Linus Torvalds <torvalds@transmeta.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: RE: Why HZ on i386 is 100 ?
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On Tue, 16 Apr 2002, Chen, Kenneth W wrote:

> If you change HZ to 1000, you need to change PROC_CHANGE_PENALTY
> accordingly.  Otherwise, process would get preempted before its time slice
> gets expired.  The net effect is more context switch than necessary, which
> could explain the 10% difference.

that might be the case. i was not running the latsched sampler during that
test, that would have helped me in detecting extra task bounces/cs



- Davide



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