Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261779AbUJYMpY (ORCPT ); Mon, 25 Oct 2004 08:45:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261776AbUJYMpY (ORCPT ); Mon, 25 Oct 2004 08:45:24 -0400 Received: from smtp206.mail.sc5.yahoo.com ([216.136.129.96]:50860 "HELO smtp206.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S261779AbUJYMoB (ORCPT ); Mon, 25 Oct 2004 08:44:01 -0400 Message-ID: <417CF50A.6080702@yahoo.com.au> Date: Mon, 25 Oct 2004 22:43:54 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.2) Gecko/20040820 Debian/1.7.2-4 X-Accept-Language: en MIME-Version: 1.0 To: Sami Farin <7atbggg02@sneakemail.com> CC: linux-kernel Mailing List , Ingo Molnar Subject: Re: Linux 2.6.9 latencies: scheduler bug? References: <20041024212618.GA19377@m.safari.iki.fi> <20041025120021.GA9917@m.safari.iki.fi> In-Reply-To: <20041025120021.GA9917@m.safari.iki.fi> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1730 Lines: 43 Sami Farin wrote: > On Mon, Oct 25, 2004 at 12:26:18AM +0300, Sami Farin wrote: > ... > >>while that's running, "rtc_latencytest 1024" has max latencies of 253ms. >>$BLOCKLIST has around two thousand lines. >>http://safari.iki.fi/ip_tables_original_maxlat_253ms.png >>from pressing sysrq+p while it was running, I guesstimated one evil spot >>and added cond_resched() in there :) >>http://safari.iki.fi/ip_tables_cond_resched.png >>at 5s I started the script. > > > forget this stupid ip_tables.c patch, latencies have nothing to do with > netfilter code, but bad interaction between xmms, rtc_latencytest > and iptables. I now get at max 3.1s (yup, 3100000us) latencies. > http://safari.iki.fi/2.6.9-xmms-fun-1.png > if you want to reproduce this: > 1) run "rtc_latencytest 1024" (can't reproduce with "rtc_latencytest 512") > 2) press play in xmms > 3) start iptables-script > > xmms has to be prepared first. > a) put it in repeat mode > b) start playing >= 2 files (like that short testcase.mp3 from lame) > c) remove the files while xmms is playing > d) wait till xmms has played all of the selected files > e) press stop [now then you press play in 2), xmms does silly infinite > loop without delays while trying to open the songs] > > please give me patches to try, 3.1s is really evil 8-) > Don't think I've tried rtc_latency test. A quick search didn't turn up its source code... So... stupid question, is rtc_latencytest running with a realtime scheduling policy? - 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/