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Date: Thu, 09 Jul 2009 21:43:35 +0300
From: Andriy Gapon <avg@freebsd.org>
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Subject: Re: dtrace users opinion solicited (timestamps)
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on 09/07/2009 21:02 Marius Nünnerich said the following:
> What about atomically changing tsc_freq every time the frequency is changed?

This is what actually  does happen, but it doesn't help.

Say, there is a moment T1 when TSC has value N and tsc_freq is X, and moment T2
when when TSC value (N + 1) and tsc_freq is 10*X.
So the formula gives:

t1 = N / X
t2 = (N+1) / (10*X)


-- 
Andriy Gapon