From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752908AbYGEOOu (ORCPT ); Sat, 5 Jul 2008 10:14:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750826AbYGEOOn (ORCPT ); Sat, 5 Jul 2008 10:14:43 -0400 Received: from www.church-of-our-saviour.ORG ([69.25.196.31]:46260 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750848AbYGEOOn (ORCPT ); Sat, 5 Jul 2008 10:14:43 -0400 Date: Sat, 5 Jul 2008 10:13:35 -0400 From: Theodore Tso To: Arjan van de Ven Cc: akpm@linux-foundation.org, jens.axboe@oracle.com, linux-kernel@vger.kernel.org Subject: Re: PATCH] fix potential latency issues in JBD's journal code Message-ID: <20080705141335.GB20240@mit.edu> Mail-Followup-To: Theodore Tso , Arjan van de Ven , akpm@linux-foundation.org, jens.axboe@oracle.com, linux-kernel@vger.kernel.org References: <20080704192929.2c4dd4ca@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080704192929.2c4dd4ca@infradead.org> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@mit.edu X-SA-Exim-Scanned: No (on thunker.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Acked-by: "Theodore Ts'o" I will make the corresponding change for ext4. Is the "Properly notify block layer of sync writes" going to be pushed to mainline? I can't add SWRITE_SYNC to the ext4 tree without growing a dependency to this patch. > This patch modifies two key places that submit IO that then immediately will > get waited on. The JBD code is slightly convoluted, but after some chasing of > abstraction layers, these instances seem to really be of this pattern. > There's one case in checkpoint.c which is another candidate, but I've not > been able to get my head around the code enough to verify that that one > really is of this pattern as well, so for now I'll leave that one as is. You mean the ll_rw_block() SWRITE in __flush_patch? Yep, seems to be of the same pattern. - Ted