From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 21 Feb 2001 19:23:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 21 Feb 2001 19:23:24 -0500 Received: from smtp03.mrf.mail.rcn.net ([207.172.4.62]:37567 "EHLO smtp03.mrf.mail.rcn.net") by vger.kernel.org with ESMTP id ; Wed, 21 Feb 2001 19:23:16 -0500 Date: Wed, 21 Feb 2001 18:33:13 -0500 From: "Michael B. Allen" To: Wayne Whitney Cc: linux-kernel@vger.kernel.org Subject: Re: 2.2.17 Lockup and ATA-66/100 forced bit set (WARNING) Message-ID: <20010221183313.A3487@angus.foo.net> In-Reply-To: <20010221173439.A3178@angus.foo.net> <200102212348.f1LNm6X02792@adsl-209-76-109-63.dsl.snfc21.pacbell.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: <200102212348.f1LNm6X02792@adsl-209-76-109-63.dsl.snfc21.pacbell.net>; from whitney@math.berkeley.edu on Wed, Feb 21, 2001 at 03:48:06PM -0800 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 21, 2001 at 03:48:06PM -0800, Wayne Whitney wrote: > > append="idebus=66 ide0=ata66" > > The idebus=66 part is incorrect. This option refers to the clock of > the PCI bus the IDE controller is on and should rarely be changed from > the default of 33MHz (i.e., only if you are overclocking the PCI bus). Ah, well I just added that based on the end of this boot message: ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx > >kernel: VP_IDE: ATA-66/100 forced bit set (WARNING)!! > > I'm sure this is just telling you that you passed the ide0=ata66 > parameter. Usually it is best not to do this--the driver should run > your chipset/drive as fast as possible without 'forcing' the > configuration. Of course, testing with hdparm -t is considered the > definitive way to check how fast the interface is running. If I don't add it hdparm -t /dev/hda reports: Timing buffered disk reads: 64 MB in 16.46 seconds = 3.89 MB/sec Then if I do hdparm -d1 -X66 /dev/hda I get: /dev/hda: setting using_dma to 1 (on) setting xfermode to 66 (UltraDMA mode2) using_dma = 1 (on) [root@nano /root]# hdparm -t /dev/hda /dev/hda: Timing buffered disk reads: 64 MB in 4.04 seconds = 15.84 MB/sec Now if I add it via append, reboot and do hdparm -t I get: Timing buffered disk reads: 64 MB in 3.70 seconds = 17.30 MB/sec This last difference is consistently better. Weird. All your other bets were right too. Thanks Wayne, Mike -- signature pending