amd64/152405: wrong user time is reported when CPU frequency throttled.

[Andriy Gapon]

The following reply was made to PR amd64/152405; it has been noted by GNATS.

From: Andriy Gapon <avg at freebsd.org>
To: =?UTF-8?B?IktPSUUgSGlkZXRha2EgKOmvieaxn+iLsemahu+8oOaVsOeQhuaKgOeglCki?=
 <koie at suri.co.jp>
Cc: bug-followup at freebsd.org
Subject: Re: amd64/152405: wrong user time is reported when CPU frequency
 throttled.
Date: Wed, 24 Nov 2010 16:19:24 +0200

 on 24/11/2010 15:54 Andriy Gapon said the following:
 > Anyway, it seems that I missed the real cause of this problem and the excellent
 > explanation by Bruce.
 
 Could you please try the following (work-in-progress) patch?
 http://people.freebsd.org/~avg/tsc-cpu_ticks.diff
 
 I expect that it should improve accuracy for your testcase, but may penalize
 system performance to certain degree.
 
 As mav@ has said, performance, accuracy, powerstate management - pick any two of
 the three.  OTOH, I am not sure by how much the performance could be affected.
 
 -- 
 Andriy Gapon