From: Eric Sandeen Subject: Re: [PATCH] ext3: wait on all pending commits in ext3_sync_fs Date: Thu, 18 Dec 2008 19:34:14 -0600 Message-ID: <494AFA16.2010004@redhat.com> References: <4908C951.2000309@redhat.com> <20081103184426.GA31894@ajones-laptop.nbttech.com> <20081103113318.35b0c266.akpm@linux-foundation.org> <20081103201428.GB30565@ajones-laptop.nbttech.com> <20081218231707.GB20092@atrey.karlin.mff.cuni.cz> <494ADEB3.8010109@redhat.com> <20081219002752.GE8424@duck.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Arthur Jones , Andrew Morton , "linux-ext4@vger.kernel.org" , "sct@redhat.com" , "linux-kernel@vger.kernel.org" To: Jan Kara Return-path: Received: from mx2.redhat.com ([66.187.237.31]:60438 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753540AbYLSBeX (ORCPT ); Thu, 18 Dec 2008 20:34:23 -0500 In-Reply-To: <20081219002752.GE8424@duck.suse.cz> Sender: linux-ext4-owner@vger.kernel.org List-ID: Jan Kara wrote: >> In looking at what we have today, I wonder if we can make things smarter >> so that we don't commit empty transactions in any case? > Probably it does not make sence to commit such transactions and we might > save some time in sync paths if we do so. So yes, I think skipping empty > transaction commit might be worthwhile and it shouldn't be hard to do > either. But I'd give it serious testing just in case some unexpectedly > relies on this behaviour - wouldn't this interfere e.g. with sync > transaction batching autotuning code? Untested patch below... > Honza Cool, thanks! This's stop: # sync from spinning up disks under idle filesystems too, I think. I was looking at something similar but was still working out how many things to check before deciding if the transaction was in fact empty. :) -Eric