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I am using Marss cycle-accurate simulator, which uses QEMU. It is a full system simulator and gives both user and kernel stats.

However, even if I take only user-stats, the statistics vary a lot between different runs. I have asked this question on marss site, but could not get a good answer.

I was wondering if it has something to do with qemu. Or any qemu option/variation, that can make simulation deterministic. I tried using -icount auto and still some variation is there.

With simplescalar eio files, I have never observed any variation.

Can anyone explain why I get different stats for identical runs?

share|improve this question
I don't have any input on the question, but in the case of cross-posting, avoid it and instead flag your question, asking a moderator to migrate it. – Paul Nov 22 '11 at 22:47
@Paul Thanks. I did not know that, but will do so in future. – user984260 Nov 25 '11 at 21:34

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