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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] Timer/clock for Linux
Date: Wed, 26 Apr 2006 15:21:07 +0100
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To: Jamie Lokier <jamie@shareable.org>
Cc: qemu-devel@nongnu.org

On Wednesday 26 April 2006 14:01, Jamie Lokier wrote:
> Paul Brook wrote:
> > One solution (which is also desirable for other reasons) is to
> > implement some form of guest cycle counting based on the
> > instructions actually executed.  Then use that as the high-precision
> > timesource, and use some for of adaptive method to keep host and
> > guest clocks in sync.
>
> That's what I meant, expressed more clearly, except that I meant to
> count guest time based on the real time spent executing guest code,
> rather than counting individual instructions.  Thanks!

How do you propose doing that? It implies you have some way of interrupting 
the guest after it has executed a small amount of guest code, where "small" 
is less than the resolution+latency of host timer interrupts.

Paul