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Subject: Re: freebsd 13 ryzen micro stutter
To: Santiago Martinez <sm@codenetworks.net>, freebsd-current@freebsd.org
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From: Andriy Gapon <avg@FreeBSD.org>
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Date: Mon, 5 Apr 2021 16:03:12 +0300
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On 27/03/2021 12:54, Santiago Martinez wrote:
> Hi, i have the same output as @Nils B. If i run with steal =2 and dtrace the
> micro stutter doesn't happen but as soon as i stop the dtrace script it the
> stutters come back again.

It seems that DTrace creates some extra CPU load that masks the problem.
So, I guess that DTrace produced traces won't have many clues, if any at all.
I wonder if KTR tracing would be better in this respect.

-- 
Andriy Gapon