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, 7 Dec 2002 01:07:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 7 Dec 2002 01:07:19 -0500 Received: from packet.digeo.com ([12.110.80.53]:26067 "EHLO packet.digeo.com") by vger.kernel.org with ESMTP id ; Sat, 7 Dec 2002 01:07:19 -0500 Message-ID: <3DF191DA.A88E2C1A@digeo.com> Date: Fri, 06 Dec 2002 22:14:50 -0800 From: Andrew Morton X-Mailer: Mozilla 4.79 [en] (X11; U; Linux 2.5.46 i686) X-Accept-Language: en MIME-Version: 1.0 To: Con Kolivas CC: linux kernel mailing list Subject: Re: [BENCHMARK] max bomb segment tuning with read latency 2 patch in contest References: <200212071620.05503.conman@kolivas.net> <3DF18D38.F493636C@digeo.com> <200212071709.50023.conman@kolivas.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 07 Dec 2002 06:14:51.0040 (UTC) FILETIME=[F38BDA00:01C29DB7] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Con Kolivas wrote: > > ... > >If the SMP machine is using scsi then that tends to make the elevator > >changes less effective. Because the disk sort-of has its own internal > >elevator which in my testing on a Fujitsu disk has the same ill-advised > >design as the kernel's elevator: it treats reads and writes in a similar > >manner. > > These are ide disks, in the same format as those used in the UP machine, so it > still should be showing the same effect? I think higher numbers in UP would > increase the resolution more for these results - apart from that is there any > disadvantage to doing it in SMP? If you think it's worth running them in UP > mode I'll do that. Oh, OK. I was guessing, and guessed wrong. No, I don't expect you'd see much difference switching to UP for those tests which are sensitive to the IO scheduler policy.