From owner-freebsd-mobile Mon Apr 16 17:48:59 2001 Delivered-To: freebsd-mobile@freebsd.org Received: from meow.osd.bsdi.com (meow.osd.bsdi.com [204.216.28.88]) by hub.freebsd.org (Postfix) with ESMTP id 7DF7237B446; Mon, 16 Apr 2001 17:48:55 -0700 (PDT) (envelope-from jhb@FreeBSD.org) Received: from laptop.baldwin.cx (john@jhb-laptop.osd.bsdi.com [204.216.28.241]) by meow.osd.bsdi.com (8.11.2/8.11.2) with ESMTP id f3H0mkG81917; Mon, 16 Apr 2001 17:48:46 -0700 (PDT) (envelope-from jhb@FreeBSD.org) Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <200104162003.f3GK36513708@mass.dis.org> Date: Mon, 16 Apr 2001 17:48:13 -0700 (PDT) From: John Baldwin To: Mike Smith Subject: Re: observation: clock slows down when battery power gets low Cc: f-mobile , parv , (Nate Williams) Sender: owner-freebsd-mobile@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On 16-Apr-01 Mike Smith wrote: >> > just an observation... on dell i5000e, clock slowed down >> > by about an hour and 10 minutes. didn't see anything else >> > happening. i instinctively pressed the "power" button >> > when "power" led was not shining. nothing bad happened (of >> > course, apm is disabled.). >> >> I think apm must be enabled for it to recognize the 'slowing' clock and >> deal with things correctly. >> >> Either that or completely disable power-savings... > > No, just don't use the TSC. The BIOS is winding the CPU clock back to > reduce power consumption, but the TSC code has no way of knowing that > this is going on. > > Again - do not use the TSC. Got it yet? 8) That would be easier if not doing so wasn't so cryptic to figure out from a non-kernel hacker perspective, Mike. :) Parv, You want to do: sysctl -w kern.timecounter.hardware=i8254 To make it more permament and easier, you can just stick kern.timecounter.hardware=i8254 in /etc/sysctl.conf. We really should use hte i8254 by default on laptops. I have acpi turned on so the system even knows that it has a CPU that throttles, but it still uses the TSC by default. *sigh* -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.baldwin.cx/~john/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-mobile" in the body of the message