Date: Tue, 17 Aug 2004 02:19:57 +0200 From: Arne Schwabe <arne@rfc2549.org> To: Colin Percival <colin.percival@wadham.ox.ac.uk> Cc: freebsd-mobile@freebsd.org Subject: Re: Enhanced SpeedStep driver available Message-ID: <86zn4uwr82.fsf@kamino.rfc1149.org> In-Reply-To: <6.1.0.6.1.20040816074348.03f99338@popserver.sfu.ca> (Colin Percival's message of "Mon, 16 Aug 2004 08:06:30 -0700") References: <6.1.0.6.1.20040816074348.03f99338@popserver.sfu.ca>
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Colin Percival <colin.percival@wadham.ox.ac.uk> writes: > Thanks to everyone who has been sending me data about their > processors (and in particular, the 90nm versions), I now have > a first draft of a Enhanced SpeedStep driver available. For > people with the appropriate processors (Pentium M only), this > makes it possible to adjust the cpu frequency via a new sysctl > (hw.est_curfreq), and have the cpu voltage adjusted at the > same time. > I've also put together a very simple control daemon which > reads kern.cp_time every second and adjusts the cpu frequency > based on the fraction of cpu time which is idle. This increases > my laptop's battery life by around 40%. Works for me :)) a simple speedtest confirms that: openssl speed sha1 with 600 mhz: The 'numbers' are in 1000s of bytes per second processed. type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes sha1 2799.31k 8809.00k 21315.56k 33035.59k 39001.77k and then setting it to 1600 mhz: The 'numbers' are in 1000s of bytes per second processed. type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes sha1 7490.03k 23513.16k 56742.98k 87939.26k 104086.94k The numbers are about 2,7 times higher and 600 * 2,7 ~= 1600 :) One little bug: sudo sysctl hw.est_curfreq=1600 hw.est_curfreq: 600 -> 600 [2:14]arne@kamino:~/tmp/estctrl% sudo sysctl hw.est_curfreq=600 hw.est_curfreq: 1600 -> 600 [2:14]arne@kamino:~/tmp/estctrl% sudo sysctl hw.est_curfreq=1600 hw.est_curfreq: 600 -> 600 [2:14]arne@kamino:~/tmp/estctrl% sudo sysctl hw.est_curfreq=1600 hw.est_curfreq: 1600 -> 1600 For some reason, the message when I set cpu freq higher does not work Arne
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