From owner-freebsd-hackers Sun Sep 7 18:24:09 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id SAA24131 for hackers-outgoing; Sun, 7 Sep 1997 18:24:09 -0700 (PDT) Received: from tao.sinanet.com.tw ([139.175.55.224]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id SAA24071; Sun, 7 Sep 1997 18:24:00 -0700 (PDT) Received: (from ywliu1@localhost) by tao.sinanet.com.tw (8.8.5/8.8.5) id JAA14004; Mon, 8 Sep 1997 09:24:12 +0800 (CST) From: Hoffmann Yen-Wei Liu Message-Id: <199709080124.JAA14004@tao.sinanet.com.tw> Subject: Kernel clock runs inaccurately To: question@freebsd.org Date: Mon, 8 Sep 1997 09:24:11 +0800 (CST) Cc: hackers@freebsd.org X-Mailer: ELM [version 2.4ME+ PL31H (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Hi, Sorry, I don't know if this question fits in questions or hackers mailing list. I just got myself a new AMD k6-200, and I found out a major problem : it runs about 30 seconds faster per day. So two days later, it runs 2 minutes faster. However, the CMOS clock runs around 2 seconds slower per day. This is acceptable to me. After fooling around with CLK_USE_I8254_CALIBRATION and CLK_USE_I586_CALIBRATION options, I can either make it run 2 seconds slower per *hour*, or several seconds faster per minutes, but not to a acceptably inaccurate ranage. The boot verbose flag gives me the following figure inf: ... Calibrating clock(s) ... i586 clock: 199932094 Hz, i8254 clock: 1194681 Hz Calibrating clock(s) ... i586 clock: 199931374 Hz, i8254 clock: 1194663 Hz CPU: AMD K6 (199.93-MHz 586-class CPU) Origin = "AuthenticAMD" Id = 0x561 Stepping=1 Features=0x8001bf ... Also, even looking into isa/i386/clock.c cannot give me too many clues. In a word, 1) I know Pentium motherboard clock isn't accurate. But is there any workaround for me to set options or modify clock.c to make the kernel clock runs in a acceptably inaccurate range ? 2) Does changing to a new motherboard with better quality help ? 3) I run OSS/FreeBSD commercial sound driver. Does this possibly matter ? THanks for your attention. Yen-Wei Liu