From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264430AbUEDPFe (ORCPT ); Tue, 4 May 2004 11:05:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264429AbUEDPFe (ORCPT ); Tue, 4 May 2004 11:05:34 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.105]:25236 "EHLO e5.ny.us.ibm.com") by vger.kernel.org with ESMTP id S264428AbUEDPFZ (ORCPT ); Tue, 4 May 2004 11:05:25 -0400 Subject: Re: Random file I/O regressions in 2.6 From: Ram Pai To: Andrew Morton Cc: nickpiggin@yahoo.com.au, peter@mysql.com, alexeyk@mysql.com, linux-kernel@vger.kernel.org, axboe@suse.de In-Reply-To: <20040503232928.1b13037c.akpm@osdl.org> References: <200405022357.59415.alexeyk@mysql.com> <409629A5.8070201@yahoo.com.au> <20040503110854.5abcdc7e.akpm@osdl.org> <1083615727.7949.40.camel@localhost.localdomain> <20040503135719.423ded06.akpm@osdl.org> <1083620245.23042.107.camel@abyss.local> <20040503145922.5a7dee73.akpm@osdl.org> <4096DC89.5020300@yahoo.com.au> <20040503171005.1e63a745.akpm@osdl.org> <4096E1A6.2010506@yahoo.com.au> <1083631804.4544.16.camel@localhost.localdomain> <20040503232928.1b13037c.akpm@osdl.org> Content-Type: text/plain Organization: Message-Id: <1083683034.13688.7.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-5) Date: 04 May 2004 08:03:55 -0700 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2004-05-03 at 23:29, Andrew Morton wrote: > > Putting a semaphore around do_generic_file_read() or maintaining the state > as below fixes it up. > > I wonder if we should bother fixing this? I guess as long as the app is > using pread() it is a legitimate thing to be doing, so I guess we should... > > > Yes this patch makes sense. I have setup sysbench on my lab machine. Let me see how much improvement the patch provides. RP