From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932200Ab2AIPuV (ORCPT ); Mon, 9 Jan 2012 10:50:21 -0500 Received: from li9-11.members.linode.com ([67.18.176.11]:53342 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932123Ab2AIPuS (ORCPT ); Mon, 9 Jan 2012 10:50:18 -0500 Date: Mon, 9 Jan 2012 10:50:16 -0500 From: "Ted Ts'o" To: Shantanu Goel Cc: Kernel Subject: Re: [PATCH] ext4: Fix up range_end offset in range cyclic writeback Message-ID: <20120109155016.GD22175@thunk.org> Mail-Followup-To: Ted Ts'o , Shantanu Goel , Kernel References: <1325993012.29526.YahooMailNeo@web38004.mail.mud.yahoo.com> <20120109151707.GB22175@thunk.org> <1326123988.9602.YahooMailNeo@web38004.mail.mud.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1326123988.9602.YahooMailNeo@web38004.mail.mud.yahoo.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on test.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 09, 2012 at 07:46:28AM -0800, Shantanu Goel wrote: > > Thanks for confirming the fix is good.  We noticed that kupdate > writebacks were happening at irregular intervals So this was a performance issue that led you to this investigation? How much of a performance issue are we talking about? If it's a correctness issue that might lead to data loss because fsync() wasn't doing its jobs, that's obviously higher priority than a performance issue. Again, I just wanted to characterize this correctly in the commit --- BTW, this is good stuff to include in the commit description so in the future, developers trying to go through the history can understand why a particular patch is important (perhaps to backport into an enterprise distro release, etc.) Thanks, regards, - Ted