Date: Sun, 21 Mar 2004 02:09:39 +0100 (CET)
From: Tim Schmielau <tim@physik3.uni-rostock.de>
To: Peter Williams <peterw@aurema.com>
cc: Arjan van de Ven <arjanv@redhat.com>,
       Stefan Smietanowski <stesmi@stesmi.com>,
       Micha Feigin <michf@post.tau.ac.il>, John Reiser <jreiser@BitWagon.com>,
       lkml <linux-kernel@vger.kernel.org>
Subject: Re: finding out the value of HZ from userspace
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Message-ID: <Pine.LNX.4.53.0403210202120.24035@gockel.physik3.uni-rostock.de>
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On Sun, 21 Mar 2004, Peter Williams wrote:

> In the 2.6 kernels internal timing and task statistics (for i386 
> systems) are now kept in milliseconds where they were previously in 
> 1/100ths of a second.  By converting these statistics to 1/100ths of a 
> second for export to user space an order of magnitude (i.e. a factor of 
> 10) loss of precision occurs.

No. The statistics are not a result of full bookkeeping, but simply
gained by periodically sampling the processor state. So they don't
have a precision of 1/1000th of a second anyways.


Tim
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