From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 28 Sep 2002 05:12:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 28 Sep 2002 05:12:15 -0400 Received: from c16598.thoms1.vic.optusnet.com.au ([210.49.243.217]:26823 "HELO pc.kolivas.net") by vger.kernel.org with SMTP id ; Sat, 28 Sep 2002 05:12:09 -0400 Message-ID: <1033204648.3d9573a81bfa9@kolivas.net> Date: Sat, 28 Sep 2002 19:17:28 +1000 From: Con Kolivas To: Jens Axboe Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [BENCHMARK] 2.5.39 with contest 0.41 References: <1033196310.3d955316425bd@kolivas.net> <3D95670C.3239A357@digeo.com> <1033201873.3d9568d158a72@kolivas.net> <20020928090806.GI23468@suse.de> In-Reply-To: <20020928090806.GI23468@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT User-Agent: Internet Messaging Program (IMP) 3.1 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Quoting Jens Axboe : > On Sat, Sep 28 2002, Con Kolivas wrote: > > > > io_load: > > > > Kernel Time CPU Ratio > > > > 2.4.19 216.05 33% 3.19 > > > > 2.5.38 887.76 8% 13.11* > > > > 2.5.38-mm3 105.17 70% 1.55* > > > > 2.5.39 216.81 37% 3.20 > > > > > > -mm3 has fifo_batch=16. 2.5.39 has fifo_batch=32. > > That's not the only difference, btw. > > > > > mem_load: > > > > Kernel Time CPU Ratio > > > > 2.4.19 105.40 70% 1.56 > > > > 2.5.38 107.89 73% 1.59 > > > > 2.5.38-mm3 117.09 63% 1.73* > > > > 2.5.39 103.72 72% 1.53 > > > > > > 2.5's swapout is still fairly synchronously sucky. So low-latency > > > writeout could be advantageous there. This difference is probably > > > also the fifo_batch thing. Or maybe statistical? > > > > > > > > > I did some testing with your latest. 4xPIII, mem=512m, SCSI, > > > tag depth = 0, 2.5.39-mm1 candidate: > > > > > > fifo_batch=32: > > > > > > noload 2:34.53 291% > > > cpuload 2:36.20 286% > > > memload 2:19.44 333% > > > ioloadhalf 2:34.81 303% > > > ioloadfull 3:15.47 238% > > > > > > (err. memload sped it up!) > > > > > > fifo_batch=16: > > > > > > noload 2:00.03 380% > > > cpuload 2:27.62 304% > > > memload 2:22.59 326% > > > ioloadhalf 2:33.75 306% > > > ioloadfull 2:59.18 259% > > > > > > - Something went horridly wrong in the first `noload' test. > > > - fifo_batch=16 is better than 32. > > > - you see a 4x hit from io_load. I see a 1.5x hit. > > So far fifo_batch=16 looks pretty good. Doesn't quite make sense to me. > Need to bench/test some more :-) Andrew was using an older version of contest which may have been misrepresenting things as there were serious limitations in the older versions. I've directed him to the new version which has worked around (most) of the limitations. SMP on the older version was particularly bad. Con.