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From: Don Bowman <don@sandvine.com>
To: akanwar@digitarchy.com
Date: Tue, 7 Oct 2003 23:29:01 -0400 
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cc: freebsd-hackers@freebsd.org
Subject: RE: HZ = 1000 slows down application
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From: Luigi Rizzo [mailto:rizzo@icir.org]
> On Tue, Oct 07, 2003 at 06:17:04PM -0400, 
> akanwar@digitarchy.com wrote:
> > Hi Luigi, Mark,
> > 
> > Thanks for your replies.
> > 
> > We did some intensive profiling of our application. It does 
> not seem like
> > we are depending on clock ticks for any calculations.
> > 
> > On the other hand we notice that our slow iterations happen 
> almost at the
> > same instant as "microuptime went backward" messages in the 
> system log. We
> 

I think you need kern.timecounter.method=1 in sysctl.conf.