From mboxrd@z Thu Jan 1 00:00:00 1970 From: tytso@mit.edu Subject: Re: [PATCH 3/4] writeback: pay attention to wbc->nr_to_write in write_cache_pages Date: Sun, 25 Apr 2010 22:45:27 -0400 Message-ID: <20100426024527.GD13043@thunk.org> References: <1271731314-5893-1-git-send-email-david@fromorbit.com> <1271731314-5893-4-git-send-email-david@fromorbit.com> <20100425033315.GC667@thunk.org> <20100426014908.GD11437@dastard> <20100426024302.GC13043@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: Dave Chinner , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, xfs@oss.sgi.com Return-path: Received: from THUNK.ORG ([69.25.196.29]:49534 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752697Ab0DZCp3 (ORCPT ); Sun, 25 Apr 2010 22:45:29 -0400 Content-Disposition: inline In-Reply-To: <20100426024302.GC13043@thunk.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Sun, Apr 25, 2010 at 10:43:02PM -0400, tytso@MIT.EDU wrote: > Have you tested with multiple files that are subject to writeout at > the same time? After all, if your I/O allocator does a great job of > keeping the files contiguous in chunks larger tham 4MB, then if you > have two or more files that need to be written out, the page allocator > will round robin between the two files in 4MB chunks, and that might > not be considered an ideal I/O pattern. Argh. Sorry for not proof reading better before hitting the send key.... s/tham/than/ s/page allocator/writeback code/ - Ted