Date: Thu, 17 May 2007 05:31:30 +1000 From: Peter Jeremy <peterjeremy@optushome.com.au> To: Nate Lawson <nate@root.org> Cc: acpi@freebsd.org Subject: Re: PowerTOP for FreeBSD ? Message-ID: <20070516193130.GG1162@turion.vk2pj.dyndns.org> In-Reply-To: <464AAC1E.7060002@root.org> References: <20070515050404.GK49628@obelix.dsto.defence.gov.au> <1179249135.1149.21.camel@vonnegut> <20070516032813.GB3773@obelix.dsto.defence.gov.au> <464AAC1E.7060002@root.org>
next in thread | previous in thread | raw e-mail | index | archive | help
--IS0zKkzwUGydFO0o Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2007-May-16 00:00:46 -0700, Nate Lawson <nate@root.org> wrote: >Normally timers tick every 1 us on FreeBSD. Unless something has changed massively, tradtiionally, hardclock interrupts every 1msec and statclick interrupts at 128Hz (approx 8msec). > Most interrupts are >serviced with no work to be performed, so it's just wasted computation. Using the lapic timer is an excellent example of this. By default it runs at 2000Hz to run hardclock() every 1msec and statclock() every 7.5 msec - just under 50% of the interrupts are completely wasted. --=20 Peter Jeremy --IS0zKkzwUGydFO0o Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (FreeBSD) iD8DBQFGS1wS/opHv/APuIcRAiISAJ0Xoeh6+B/LFxhNpy8qYowt2j/55wCeKr7H aCqpIZqeP/fQMt6rdPcl4A4= =n3Ln -----END PGP SIGNATURE----- --IS0zKkzwUGydFO0o--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20070516193130.GG1162>