Date: Tue, 22 Jun 2004 14:45:36 -0500
From: Brent Casavant <bcasavan@sgi.com>
Reply-To: Brent Casavant <bcasavan@sgi.com>
To: Albert Cahalan <albert@users.sourceforge.net>
cc: Andrew Morton OSDL <akpm@osdl.org>,
       linux-kernel mailing list <linux-kernel@vger.kernel.org>, ak@suse.de
Subject: Re: [PATCH] Add kallsyms_lookup() result cache
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 <1087650315.8188.915.camel@cube>
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On Sat, 19 Jun 2004, Albert Cahalan wrote:

> I'm not so sure anything needs to be fixed, save for SGI upgrading
> to a more modern procps. There are many more important things:

OK, I looked into this more closely, and gave procps 3.2.1 a spin.
This gives us a similar speedup (top now only consumes 60% of a CPU)
to that which I obtained by cacheing symbol lookups and using an old
procps.  This difference is certainly explainable by top now only
obtaining wchan information for displayed processes.

60% is far better than 800%, so this is certainly progress.  However
60% is also still quite a bit of CPU time.  I'll spend some cycles
trying to whittle it down some more, but I'm not all that hopeful.

Thanks for the discussion, it was certainly enlightening.

Brent

-- 
Brent Casavant             bcasavan@sgi.com        Forget bright-eyed and
Operating System Engineer  http://www.sgi.com/     bushy-tailed; I'm red-
Silicon Graphics, Inc.     44.8562N 93.1355W 860F  eyed and bushy-haired.
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