From: Jan Engelhardt <jengelh@computergmbh.de>
To: Rene Herman <rene.herman@gmail.com>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [RFT] Port 0x80 I/O speed
Date: Thu, 13 Dec 2007 01:13:52 +0100 (CET) [thread overview]
Message-ID: <Pine.LNX.4.64.0712130110510.32346@fbirervta.pbzchgretzou.qr> (raw)
In-Reply-To: <Pine.LNX.4.64.0712130041590.32346@fbirervta.pbzchgretzou.qr>
On Dec 13 2007 00:54, Jan Engelhardt wrote:
>
>Transmeta TM5800 CPU with nominal frequency 933 MHz, but it has a
>hardware(!) 'ondemand' governor over the range of frequencies that
>the user allowed scaling over, irrespective of the software governor.
>(That is, if the CPU can do 300,533 and 933 MHz, and setting the
>min/max to 300/533 will cause the hardware to 'ondemand' between 300
>and 533 only. And that even if 'performance' is set on the software
>side - so the only way to enforce 'performance' is to actually set
>min=933.)
>
>00:46 takeshi:../cpu0/cpufreq # echo 300000 >scaling_min_freq
>00:46 takeshi:../cpu0/cpufreq # echo 933000 >scaling_max_freq
>00:42 takeshi:/dev/shm # for ((x=1;x<=10;++x)); do ./port80 ; done
>cycles: out 1514, in 584
^ most likely 300 MHz state
>cycles: out 1371, in 516
^ 533 MHz state
>cycles: out 1291, in 472
^ ??
>cycles: out 1304, in 437
^ ??
>cycles: out 1308, in 410
^ ??
>cycles: out 1315, in 419
^ 933 MHz state
>cycles: out 1315, in 419
>cycles: out 1314, in 419
>cycles: out 1315, in 420
>cycles: out 1315, in 419
...this is in stark contrast to values of other users, where,
skimming through the mails, higher cpu frequencies yields
higher out/in values, but not so on TM5800. Highly interesting.
next prev parent reply other threads:[~2007-12-13 0:14 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-12-11 23:31 [RFT] Port 0x80 I/O speed Rene Herman
2007-12-11 23:40 ` Maxim Levitsky
2007-12-11 23:44 ` Rene Herman
2007-12-12 0:14 ` Maxim Levitsky
2007-12-12 0:27 ` Rene Herman
2007-12-11 23:43 ` Alejandro Riveira Fernández
2007-12-11 23:51 ` Rene Herman
2007-12-12 0:09 ` Alejandro Riveira Fernández
2007-12-12 0:16 ` Rene Herman
2007-12-12 11:43 ` Alejandro Riveira Fernández
2007-12-12 21:02 ` H. Peter Anvin
[not found] ` <Pine.LNX.4.61.0712120753210.4443@chaos.analogic.com>
2007-12-12 13:20 ` Rene Herman
2007-12-12 13:23 ` linux-os (Dick Johnson)
2007-12-11 23:55 ` Nigel Cunningham
2007-12-12 0:01 ` Rene Herman
2007-12-12 2:07 ` Nigel Cunningham
2007-12-12 1:19 ` Alistair John Strachan
2007-12-12 1:28 ` Randy Dunlap
2007-12-12 1:40 ` Mike Lampard
2007-12-12 5:23 ` Kyle McMartin
2007-12-12 7:18 ` Rene Herman
2007-12-13 2:41 ` H. Peter Anvin
2007-12-12 19:25 ` H. Peter Anvin
2007-12-12 19:32 ` Andi Kleen
2007-12-12 19:43 ` H. Peter Anvin
2007-12-12 8:17 ` Paolo Ornati
2007-12-12 8:38 ` Edwin de Caluwé
2007-12-12 8:35 ` Dave Young
2007-12-12 8:48 ` Jiri Slaby
2007-12-12 11:25 ` Jiri Slaby
2007-12-12 15:50 ` Rene Herman
2007-12-12 15:53 ` Rene Herman
2007-12-12 18:44 ` H. Peter Anvin
2007-12-12 19:19 ` Rene Herman
2007-12-13 15:19 ` Jiri Slaby
2007-12-12 8:59 ` Juergen Beisert
2007-12-12 14:30 ` Rene Herman
2007-12-12 15:12 ` Juergen Beisert
2007-12-12 9:55 ` Luciano Rocha
2007-12-12 9:57 ` Romano Giannetti
2007-12-12 16:27 ` Rene Herman
2007-12-12 10:28 ` Peter Zijlstra
2007-12-12 10:34 ` Dave Haywood
2007-12-12 11:57 ` Ville Syrjälä
2007-12-13 16:42 ` Ville Syrjälä
2007-12-12 16:16 ` John Stoffel
2007-12-12 16:39 ` Olivér Pintér
2007-12-12 16:53 ` Ondrej Zary
2007-12-12 17:00 ` H. Peter Anvin
2007-12-12 16:59 ` Cyrill Gorcunov
2007-12-12 17:27 ` Török Edwin
2007-12-12 18:54 ` David P. Reed
2007-12-12 18:39 ` SL Baur
2007-12-12 19:06 ` Rene Herman
2007-12-12 21:32 ` Jesper Juhl
2007-12-12 23:54 ` Jan Engelhardt
2007-12-13 0:13 ` Jan Engelhardt [this message]
2007-12-13 2:06 ` H. Peter Anvin
2007-12-22 22:27 ` Bauke Jan Douma
2007-12-12 5:06 Chris Holvenstot
2007-12-12 11:20 linux
2007-12-12 12:35 ` Paolo Ornati
2007-12-12 14:48 ` Rene Herman
[not found] <9zmRR-3pA-25@gated-at.bofh.it>
2007-12-13 16:27 ` James Kosin
2007-12-13 22:07 ` Rene Herman
2007-12-13 22:30 ` Jesper Juhl
2007-12-13 22:37 ` Rene Herman
[not found] <9A0cz-7xy-13@gated-at.bofh.it>
[not found] ` <9A0cz-7xy-11@gated-at.bofh.it>
[not found] ` <9A4pU-69z-15@gated-at.bofh.it>
2007-12-14 14:08 ` James Kosin
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