Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268055AbUIKAfe (ORCPT ); Fri, 10 Sep 2004 20:35:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268056AbUIKAfe (ORCPT ); Fri, 10 Sep 2004 20:35:34 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.103]:8954 "EHLO e3.ny.us.ibm.com") by vger.kernel.org with ESMTP id S268055AbUIKAfL (ORCPT ); Fri, 10 Sep 2004 20:35:11 -0400 Subject: Re: [Patch 0/6]: Cleanup and rbtree for ext3 reservations in 2.6.9-rc1-mm4 From: Mingming Cao To: Stephen Tweedie Cc: Andrew Morton , linux-kernel@vger.kernel.org, pbadari@us.ibm.com, Ram Pai In-Reply-To: <200409071302.i87D2Dus030892@sisko.scot.redhat.com> References: <200409071302.i87D2Dus030892@sisko.scot.redhat.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Mailer: Ximian Evolution 1.0.8 (1.0.8-10) Date: 10 Sep 2004 17:34:44 -0700 Message-Id: <1094862886.1637.7078.camel@w-ming2.beaverton.ibm.com> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2308 Lines: 54 On Tue, 2004-09-07 at 06:02, Stephen Tweedie wrote: > The patches in the following set contain several cleanups for ext3 > reservations, fix a reproducable SMP race, and turn the per-superblock > linear list of reservations into an rbtree for better scaling. > These changes have been in rawhide for a couple of weeks, and have > been undergoing testing both within Red Hat and at IBM. > We have run several tests on this set of the reservation changes. We compared the results w/o reservation, rbtree based reservation vs link list based reservation. Here is the tiobench sequential test results.Note that 2.6.8.1-mm4 kernel include the double link based per-fs reservation tree. tiobench sequential write throughputs ============================================================ Threads no reservation 2.6.8.1-mm4 2.6.8.1-mm4+rbtree patch 1 29 29 29 4 3 29 29 8 4 28 28 16 3 27 27 32 4 27 27 64 3 27 27 128 2 20 25 256 1 20 24 We did see the rbtree changes scales better on more than 128 threads. We also run tio random tests, did not see throughput regression there. We also re-run the dbench, test results showing that these two reservations(rbtree based vs link based) performs almost equally well. dbench average throughputs on 4 runs ================================================== Threads no reservation 2.6.8.1-mm4 2.6.8.1-mm4_rbtree 1 97 93 96 4 234 250 213 8 201 213 213 16 156 168 169 32 73 106 105 64 38 65 67 We had some concerns about the cpu cost for seeky random write workload with all the reservation changes before. We are doing some tests in that area too. Mingming - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/