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Date: Fri, 10 Jul 2009 08:45:33 +0300
From: Andriy Gapon <avg@freebsd.org>
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To: David Schultz <das@freebsd.org>, freebsd-current@freebsd.org
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Subject: Re: dtrace users opinion solicited (timestamps)
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on 09/07/2009 22:39 David Schultz said the following:
> Doesn't Solaris DTRT and compensate for TSC frequency changes?
> Why can't we do the same thing?

That very well may be. I haven't thoroughly checked but I think that even we are
 doing the right thing when we use TSC as a timecounter.
But at this moment I am looking for a quick/simple and "sufficiently good" fix
for the bigger problems with DTrace timestamping (kern/127441).

Another side of the "simplicity" is that the timestamp function for DTrace needs
to be fast and should not itself be probed.

-- 
Andriy Gapon