From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030186AbVI1C4R (ORCPT ); Tue, 27 Sep 2005 22:56:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965259AbVI1C4Q (ORCPT ); Tue, 27 Sep 2005 22:56:16 -0400 Received: from rwcrmhc13.comcast.net ([216.148.227.118]:27553 "EHLO rwcrmhc12.comcast.net") by vger.kernel.org with ESMTP id S965257AbVI1C4Q (ORCPT ); Tue, 27 Sep 2005 22:56:16 -0400 Date: Tue, 27 Sep 2005 22:55:20 -0400 (Eastern Daylight Time) From: Parag Warudkar To: david.ronis@mcgill.ca cc: linux-kernel@vger.kernel.org Subject: RE: problem with 2.6.13.[0-2] Message-ID: Organization: Not Much But I Keep Trying X-X-Sender: kernel-stuff@mail.comcast.net MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > DMA is on in both 2.6.12.6 and in 2.6.13.2. Here's what hdparm > /dev/hda gives: > > in 2.6.12.6: > > /dev/hda: > multcount = 16 (on) > IO_support = 0 (default 16-bit) > unmaskirq = 0 (off) > using_dma = 1 (on) > keepsettings = 0 (off) > readonly = 0 (off) > readahead = 256 (on) > geometry = 65535/16/63, sectors = 195371568, start = 0 > > in 2.6.13.2 it's the same, except for > > multcount = 0 (off) > > Could this be the problem, and if so, would setting multcount to on > fix it? (I take it hdparm -m 16 /dev/hda would do it) I doubt if multcount will make a difference, but you can try. Probably next best thing to do is profile the slow kernel to find where it is spending time. (pass profile=2 on kernel command line and use readprofile or use oprofile). Did you try hdparm -tT /dev/hda? It's going to be slow, thats for sure from what you described but try that and then post dmesg (for both kernels) and profile results - may be someone will get a clue from that. Parag