From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Tokarev Subject: Re: ATA 4 KiB sector issues. Date: Tue, 09 Mar 2010 09:53:37 +0300 Message-ID: <4B95F071.3070400@msgid.tls.msk.ru> References: <4B947393.2050002@kernel.org> <170fa0d21003081134g491034e5v4aad4d43853e48ec@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from isrv.corpit.ru ([81.13.33.159]:56879 "EHLO isrv.corpit.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751732Ab0CIGxj (ORCPT ); Tue, 9 Mar 2010 01:53:39 -0500 In-Reply-To: <170fa0d21003081134g491034e5v4aad4d43853e48ec@mail.gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mike Snitzer Cc: "Martin K. Petersen" , Tejun Heo , "linux-ide@vger.kernel.org" , lkml , Daniel Taylor , Jeff Garzik , Mark Lord , tytso@mit.edu, "H. Peter Anvin" , hirofumi@mail.parknet.co.jp, Andrew Morton , Alan Cox , irtiger@gmail.com, Matthew Wilcox , aschnell@suse.de, knikanth@suse.de, jdelvare@suse.de, Karel Zak , Jim Meyering , Neil Brown Mike Snitzer wrote: [] > I've been keeping track of all the pieces in play, have coordinated > with kzak and jim, and have a summary that offers some amount of macro > detail (at the end I touch on parted and fdisk): > > http://people.redhat.com/msnitzer/docs/io-limits.txt What I don't see in this thread and in this document is - any mention of linux md layer. I think it is the first candidate to test the whole thing, the easiest and most important one. I mean the alignment and "recommended I/O size" and all this similar stuff. Think of a raid5 array - with all the mentioned good stuff in place fdisk should figure out to align partitions on the array stripe boundary, and should do that automatically. And this should be most easy to debug/test, since the whole thing is controllable by kernel. But apparently it does not implement anything of this sort. Adding Neilb to the Cc list....... Thanks! /mjt