From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 22 Jan 2001 18:12:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 22 Jan 2001 18:12:18 -0500 Received: from ns.virtualhost.dk ([195.184.98.160]:48135 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id ; Mon, 22 Jan 2001 18:12:15 -0500 Date: Tue, 23 Jan 2001 00:11:55 +0100 From: Jens Axboe To: Marcelo Tosatti Cc: Steven Cole , lkml Subject: Re: 2.4.1pre8 slowdown on dbench tests Message-ID: <20010123001155.B8225@suse.de> In-Reply-To: <01012208583400.01639@spc.esa.lanl.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ; from marcelo@conectiva.com.br on Mon, Jan 22, 2001 at 06:30:03PM -0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 22 2001, Marcelo Tosatti wrote: > > Jens, > > Steven is a seeing a slowdown in his results, too. > > > On Mon, 22 Jan 2001, Steven Cole wrote: > > > On Thursday 18 January 2001 14:49, Marcelo Tosatti wrote: > > > > > Steven, > > > > > > The issue is the difference between pre4 and pre8. > > > > > > Could you please try pre4 and report results ? > > > > > > Thanks > > > > Ok, here are the results for 2.4.1-pre4, along with the original -pre8 > > results. There does appear to be a slowdown. > > > > 2.4.1-pre4 > > average: 9.77876 MB/sec > > > > Throughput 10.3677 MB/sec (NB=12.9597 MB/sec 103.677 MBit/sec) > > Throughput 9.61291 MB/sec (NB=12.0161 MB/sec 96.1291 MBit/sec) > > Throughput 9.92944 MB/sec (NB=12.4118 MB/sec 99.2944 MBit/sec) > > Throughput 9.20502 MB/sec (NB=11.5063 MB/sec 92.0502 MBit/sec) > > > > 2.4.1-pre8: > > Average 9.25707 MB/sec > > > > Throughput 8.93444 MB/sec (NB=11.1681 MB/sec 89.3444 MBit/sec) > > Throughput 9.43609 MB/sec (NB=11.7951 MB/sec 94.3609 MBit/sec) > > Throughput 9.5075 MB/sec (NB=11.8844 MB/sec 95.075 MBit/sec) > > Throughput 9.15026 MB/sec (NB=11.4378 MB/sec 91.5026 MBit/sec) > > > > This was done on a dual P-III, 256MB machine. Stephen, To rule out other factors, could you try 2.4.1-pre8 with blk_started_io() and blk_finished_io() defined to nothing in include/linux/blkdev.h? This will disable the max-locked-buffers heuristic. Also, are the numbers above consistent for repeated runs (with boots in between)? -- * Jens Axboe * SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/