From owner-freebsd-hackers  Thu Nov 12 12:02:45 1998
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	Thu, 12 Nov 1998 14:02:10 -0600 (CST)
Date: Thu, 12 Nov 1998 14:02:10 -0600 (CST)
From: Shafia Kausar  <s0k9955@unix.tamu.edu>
To: Daniel Eischen <eischen@vigrid.com>
cc: luigi@labinfo.iet.unipi.it, s0k9955@unix.tamu.edu,
        freebsd-hackers@FreeBSD.ORG, mike@smith.net.au, shafiak@ee.tamu.edu
Subject: Re: Timer Granularity
In-Reply-To: <199811121807.NAA17224@pcnet1.pcnet.com>
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> > > I need a kernel clock of granularity 1ms or less, for some experiments.
> > > Which version of FreeBsd supports this granularity, other than the 3.0
> > > version? 
> > > 
> > > There is a mention of the resolution depending on the clock
> > > sources in use. Which source gives me the best resolution??
> > 
> > settin HZ=1000 or more in the kernel config file should do the job (if
> > you go too high you might start losing ticks...)
> >
> >         luigi
> 
> I set HZ to 500 just a couple of days ago on a 1-2 month old
> -current system without too many hiccups.  There still are
> a few places in the kernel that need to be fixed to use hz
> properly, though.  sysbeep is one.  Grep'ing for all the
> timeout()s and ensuring proper use of hz is a start.
>

Can I set the value of HZ in the 2.1.5 version? 

I believe the granularity of the clock in this version is 10ms. Does
changing the value of HZ change the granularity? If yes, then why is the
granularity specified as 10ms??

Thanks
-Shafia


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