From owner-freebsd-current Thu Jul 16 01:15:05 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id BAA06686 for freebsd-current-outgoing; Thu, 16 Jul 1998 01:15:05 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from ns2.cetlink.net (root@ns2.cetlink.net [209.54.54.20]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id BAA06681 for ; Thu, 16 Jul 1998 01:15:02 -0700 (PDT) (envelope-from jak@cetlink.net) Received: from EXIT10 (i485-gw.cetlink.net [209.198.15.97]) by ns2.cetlink.net (8.9.1/8.9.1) with SMTP id EAA16325; Thu, 16 Jul 1998 04:14:46 -0400 (EDT) From: jak@cetlink.net (John Kelly) To: Bruce Evans Cc: current@FreeBSD.ORG Subject: Re: tickadj -t not changing tick Date: Thu, 16 Jul 1998 08:16:45 GMT Message-ID: <35adaeab.207380020@mail.cetlink.net> References: <199807160653.QAA24751@godzilla.zeta.org.au> In-Reply-To: <199807160653.QAA24751@godzilla.zeta.org.au> X-Mailer: Forte Agent 1.5/32.451 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by hub.freebsd.org id BAA06682 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thu, 16 Jul 1998 16:53:55 +1000, Bruce Evans wrote: >>So am I correct in assuming I >>need to increase the i8254_freq value to match the true oscillator >>rate, and the kernel will adjust accordingly? > >It wouldn't hurt, but I guess you have a Pentium not running SMP or APM, >so it wouldn;t help much. Both 486's and Pentiums, so I need to understand how to tweak both i8254 and TSC. One of my 486 machines is fast by 27.68 seconds per day, so it seems I need to change its i8254_freq to 1,193,564. >Boot with -v and note the frequency calibrated relative to the RTC and >use that is input to sysctl, or use CLK_USE_I8254_CALIBRATION to set >this frequency by default. The RTC is usually more accurate than the >i8254. That's helpful too, but using the value calculated by hand from an average daily deviation as determined by ntpdate seems more precise, so I think I'll sysctl my hand-calculated value at bootup somehow. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message