From: Jeff Moyer Subject: Re: [patch/rft] jbd2: tag journal writes as metadata I/O Date: Mon, 05 Apr 2010 16:34:36 -0400 Message-ID: References: <20100405175205.GA4681@thunk.org> <20100405194803.GC23670@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, jens.axboe@oracle.com, esandeen@redhat.com To: tytso@mit.edu Return-path: Received: from mx1.redhat.com ([209.132.183.28]:18455 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756412Ab0DEUer (ORCPT ); Mon, 5 Apr 2010 16:34:47 -0400 In-Reply-To: <20100405194803.GC23670@thunk.org> (tytso@mit.edu's message of "Mon, 5 Apr 2010 15:48:03 -0400") Sender: linux-ext4-owner@vger.kernel.org List-ID: tytso@mit.edu writes: > On Mon, Apr 05, 2010 at 02:36:07PM -0400, Jeff Moyer wrote: >> > >> > What benchmark were you using to test small file writes? This looks >> > good to me as well, but we might want to do some extra benchmarking >> > just to be sure we're not accidentally introducing a performance >> > regression. >> >> iozone showed regressions for write and re-write in runs that include >> fsync timings for small files (<8MB). Here's the command line used for >> testing: >> >> iozone -az -n 4k -g 2048m -y 1k -q 1m -e > > iozone is showing performance regressions or performance improvements? > I thought the point of this patch was to improve iozone benchmarks? Sorry, Ted, what I meant to say was that iozone showed differences between deadline and cfq, where cfq's performance was much worse than deadline's. Thanks! Jeff