From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261180AbTHXCk4 (ORCPT ); Sat, 23 Aug 2003 22:40:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263376AbTHXCk4 (ORCPT ); Sat, 23 Aug 2003 22:40:56 -0400 Received: from c210-49-248-224.thoms1.vic.optusnet.com.au ([210.49.248.224]:60331 "EHLO mail.kolivas.org") by vger.kernel.org with ESMTP id S262273AbTHXCky (ORCPT ); Sat, 23 Aug 2003 22:40:54 -0400 From: Con Kolivas To: Andrew Morton Subject: Re: [PATCH]O18.1int Date: Sun, 24 Aug 2003 12:46:37 +1000 User-Agent: KMail/1.5.3 Cc: piggin@cyberone.com.au, mingo@elte.hu, linux-kernel@vger.kernel.org, lse-tech@lists.sourceforge.net References: <200308231555.24530.kernel@kolivas.org> <200308240258.33924.kernel@kolivas.org> <20030823144907.6bcce289.akpm@osdl.org> In-Reply-To: <20030823144907.6bcce289.akpm@osdl.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200308241246.38356.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 24 Aug 2003 07:49, Andrew Morton wrote: > Con Kolivas wrote: > > > >It might help if you or a buddy could get set up with volanomark on an > > > > > > > > OSDL 4-or-8-way so that you can more closely track the effect of > > > > your changes on such benchmarks. > > > > Ok here goes. > > This is on 8way: > > > > Test4: > > Average throughput = 11145 messages per second > > > > Test4-O18.1: > > Average throughput = 9860 messages per second > > > > Test3-mm3: > > Average throughput = 9788 messages per second > > > > > > So I grabbed test3-mm3 and started peeling back the patches > > and found no change in throughput without _any_ of my Oxint patches > > applied, and just Ingo's A3 patch: > > > > Test3-mm3-A3 > > Average throughput = 9889 messages per second > > > > > > Then finally I removed that patch so there were no interactivity > > patches: Test3-mm3-ni > > Average throughput = 11052 messages per second > > Well that was quick, thanks. > > Surely the only reason we see more idle time in this sort of workload is > because of runqueue imbalance: some CPUs are idle while other CPUs have > more than one runnable process. That sounds like a bug more than a > tuning/balancing thing: having no runnable tasks is a sort of binary > do-something-right-now case. > > We should be going across and pullng a task off another CPU synchronously > as soon as a runqueue is seen to be empty. The code tries to do that so > hrm. > > Ingo just sent the below patch which is related, but doesn't look like it > will fix it. I'll include this in test4-mm1, RSN. Just for the record I also tried inlining sched_clock and removing the rdtsc call entirely (and just getting the value from jiffies) and it made no measurable impact on performance. Con