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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] ARM CPU Speed simulated by Qemu?
Date: Tue, 12 Sep 2006 13:43:35 +0100
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To: qemu-devel@nongnu.org

On Tuesday 12 September 2006 08:20, Tieu Ma Dau wrote:
> Hi all,
> I found that Qemu ARM system simulates ARM926EJ-S and
> ARM1026EJ-S processor. And I found on ARM website that
> the speed of these CPUs vary from 266 to 540 MHz.
> Could you tell me the exact speed of the ARM926EJ-S
> and ARM1026EJ-S processor simulated by Qemu? It's very
> important for me to finish my report.

Qemu is not cycle accurate. There is no particularly meaningful way to 
translate between qemu performance and how fast something will run on real 
hardware.

Modern CPUs are complicated, with many factors effecting execution speed 
(pipeline interlocks, multiple levels of cache). A cycle accurate simulator 
will generally be orders of magnitude slower than qemu.

Paul