linux-kernel - (ondemand) CPU governor regression between 2.6.23 and 2.6.24

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Message-Id: <200801261506.28544.toralf.foerster@gmx.de>
Date:	Sat, 26 Jan 2008 15:06:25 +0100
From:	Toralf Förster <toralf.foerster@....de>
To:	linux-kernel@...r.kernel.org
Subject: (ondemand) CPU governor  regression between 2.6.23 and 2.6.24

I use a 1-liner for a simple performance check : "time factor 819734028463158891"
Here is the result for the new (Gentoo) kernel 2.6.24:

With the  ondemand governor of the  I get:

tfoerste@n22 ~/tmp $ time factor 819734028463158891
819734028463158891: 3 273244676154386297

real    0m32.997s
user    0m15.732s
sys     0m0.014s

With the ondemand governor the CPU runs at 600 MHz,
whereas with the performance governor I get :

tfoerste@n22 ~/tmp $ time factor 819734028463158891
819734028463158891: 3 273244676154386297

real    0m10.893s
user    0m5.444s
sys     0m0.000s

(~5.5 sec as I expected) b/c the CPU is set to 1.7 GHz.

The ondeman governor of previous kernel versions however automatically increased
the CPU speed from 600 MHz to 1.7 GHz.

My system is a ThinkPad T41, I'll attach the .config 

-- 
MfG/Sincerely

Toralf Förster
pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3

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