From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755430Ab0DCTUG (ORCPT ); Sat, 3 Apr 2010 15:20:06 -0400 Received: from mail-in-12.arcor-online.net ([151.189.21.52]:41011 "EHLO mail-in-12.arcor-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754002Ab0DCTUA (ORCPT ); Sat, 3 Apr 2010 15:20:00 -0400 X-DKIM: Sendmail DKIM Filter v2.8.2 mail-in-04.arcor-online.net 880EA33A928 Subject: Re: [Bug 12309] Large I/O operations result in slow performance and high iowait times From: Thomas Pilarski To: Henrique de Moraes Holschuh Cc: linux-kernel@vger.kernel.org, Andrew Morton , Ingo Molnar , Peter Zijlstra , Jens Axboe In-Reply-To: <20100331002549.GB9925@khazad-dum.debian.net> References: <201003162357.o2GNvkNF024562@demeter.kernel.org> <1269935094.2481.23.camel@localhost> <20100331002549.GB9925@khazad-dum.debian.net> Content-Type: text/plain; charset="UTF-8" Date: Sat, 03 Apr 2010 21:19:48 +0200 Message-ID: <1270322388.26420.56.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 (2.28.3-1.fc12) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > This problem is enormous increased, while the ultra bay disc is acceded > > with udma2 instead of udma6 (caused by another bug), > > There is a thinkpad BIOS bug that could cause that: it will not signal a > 80-wire cable when you hot-add an HD on a PATA ultrabay. Exists at least on > all T4x, including the T43. It's a SATA untrabay disk. There is a 40-wire message, but sometimes it works and sometimes not. I could not figure out, when it does and when not. > The fix is to whitelist these thinkpads for high-speed UDMA even on 40-wire > cables. The workaround is to add a kernel command line parameter (I forget > which). > > Does that match your udma2 instead of udma6 problem? Thanks. I will try it. But have to finish another project first.