Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751345AbWAJX0F (ORCPT ); Tue, 10 Jan 2006 18:26:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751355AbWAJX0F (ORCPT ); Tue, 10 Jan 2006 18:26:05 -0500 Received: from e32.co.us.ibm.com ([32.97.110.150]:2796 "EHLO e32.co.us.ibm.com") by vger.kernel.org with ESMTP id S1751345AbWAJX0E (ORCPT ); Tue, 10 Jan 2006 18:26:04 -0500 Subject: [PATCH 0/5] multiple block allocation to current ext3 From: Mingming Cao Reply-To: cmm@us.ibm.com To: Andrew Morton Cc: hch@lst.de, pbadari@us.ibm.com, "Stephen C. Tweedie" , linux-kernel , ext2-devel In-Reply-To: <1114715665.18996.29.camel@localhost.localdomain> References: <1112673094.14322.10.camel@mindpipe> <20050405041359.GA17265@elte.hu> <1112765751.3874.14.camel@localhost.localdomain> <20050407081434.GA28008@elte.hu> <1112879303.2859.78.camel@sisko.sctweedie.blueyonder.co.uk> <1112917023.3787.75.camel@dyn318043bld.beaverton.ibm.com> <1112971236.1975.104.camel@sisko.sctweedie.blueyonder.co.uk> <1112983801.10605.32.camel@dyn318043bld.beaverton.ibm.com> <1113220089.2164.52.camel@sisko.sctweedie.blueyonder.co.uk> <1113244710.4413.38.camel@localhost.localdomain> <1113249435.2164.198.camel@sisko.sctweedie.blueyonder.co.uk> <1113288087.4319.49.camel@localhost.localdomain> <1113304715.2404.39.camel@sisko.sctweedie.blueyonder.co.uk> <1113348434.4125.54.camel@dyn318043bld.beaverton.ibm.com> <1113388142.3019.12.camel@sisko.sctweedie.blueyonder.co.uk> <1114207837.7339.50.camel@localhost.localdomain> <1114659912.16933.5.camel@mindpipe> <1114715665.18996.29.camel@localhost.localdomain> Content-Type: text/plain Organization: IBM LTC Date: Tue, 10 Jan 2006 15:26:01 -0800 Message-Id: <1136935562.4901.41.camel@dyn9047017067.beaverton.ibm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-7) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2107 Lines: 56 Currently ext3_get_block() only map or allocate one block at a time. This is quite inefficient for sequential IO workload. I have posted a early implements a simply multiple block map and allocation with current ext3. The basic idea is allocating the 1st block in the existing way, and attempting to allocate the next adjacent blocks on a best effort basis. More description about the implementation could be found here: http://marc.theaimsgroup.com/?l=ext2-devel&m=112162230003522&w=2 The following the latest version of the patch: break the original patch into 5 patches, re-worked some logicals, and fixed some bugs. The break ups are: [patch 1] Adding map multiple blocks at a time in ext3_get_blocks() [patch 2] Extend ext3_get_blocks() to support multiple block allocation [patch 3] Implement multiple block allocation in ext3-try-to-allocate (called via ext3_new_block()). [patch 4] Proper accounting updates in ext3_new_blocks() [patch 5] Adjust reservation window size properly (by the given number of blocks to allocate) before block allocation to increase the possibility of allocating multiple blocks in a single call. Tests done so far includes fsx,tiobench and dbench. The following numbers collected from Direct IO tests (1G file creation/read) shows the system time have been greatly reduced (more than 50% on my 8 cpu system) with the patches. 1G file DIO write: 2.6.15 2.6.15+patches real 0m31.275s 0m31.161s user 0m0.000s 0m0.000s sys 0m3.384s 0m0.564s 1G file DIO read: 2.6.15 2.6.15+patches real 0m30.733s 0m30.624s user 0m0.000s 0m0.004s sys 0m0.748s 0m0.380s Some previous test we did on buffered IO with using multiple blocks allocation and delayed allocation shows noticeable improvement on throughput and system time. Patches against 2.6.15. Please consider to add to mm tree. Thanks! 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/