From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266820AbUHVM5o (ORCPT ); Sun, 22 Aug 2004 08:57:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266837AbUHVM5o (ORCPT ); Sun, 22 Aug 2004 08:57:44 -0400 Received: from relay.pair.com ([209.68.1.20]:32518 "HELO relay.pair.com") by vger.kernel.org with SMTP id S266820AbUHVM5l (ORCPT ); Sun, 22 Aug 2004 08:57:41 -0400 X-pair-Authenticated: 66.190.51.173 Message-ID: <41289844.6080300@cybsft.com> Date: Sun, 22 Aug 2004 07:57:40 -0500 From: "K.R. Foley" User-Agent: Mozilla Thunderbird 0.7.3 (X11/20040803) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ingo Molnar CC: Lee Revell , linux-kernel , Florian Schmidt Subject: Re: [patch] voluntary-preempt-2.6.8.1-P7 References: <20040816120933.GA4211@elte.hu> <1092716644.876.1.camel@krustophenia.net> <20040817080512.GA1649@elte.hu> <20040819073247.GA1798@elte.hu> <20040820133031.GA13105@elte.hu> <20040820195540.GA31798@elte.hu> <20040821140501.GA4189@elte.hu> <1093125390.817.22.camel@krustophenia.net> <4127E386.5000701@cybsft.com> <1093133810.817.26.camel@krustophenia.net> <20040822063500.GA20828@elte.hu> In-Reply-To: <20040822063500.GA20828@elte.hu> X-Enigmail-Version: 0.85.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime 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 Ingo Molnar wrote: > * Lee Revell wrote: > > >>On Sat, 2004-08-21 at 20:06, K.R. Foley wrote: >> >>>I just posted a similar trace of ~4141 usec from P6 here: >>> >>>http://www.cybsft.com/testresults/2.6.8.1-P6/latency-trace1.txt >>> >> >>This looks wrong: >> >>00000003 0.008ms (+0.001ms): dummy_socket_sock_rcv_skb (tcp_v4_rcv) >>00000004 0.008ms (+0.000ms): tcp_v4_do_rcv (tcp_v4_rcv) >>00000004 0.009ms (+0.000ms): tcp_rcv_established (tcp_v4_do_rcv) >>00010004 3.998ms (+3.989ms): do_IRQ (tcp_rcv_established) >>00010005 3.999ms (+0.000ms): mask_and_ack_8259A (do_IRQ) >>00010005 4.001ms (+0.002ms): generic_redirect_hardirq (do_IRQ) >>00010004 4.002ms (+0.000ms): generic_handle_IRQ_event (do_IRQ) >> >>Probably a false positive, Ingo would know better. What kind of >>stress testing were you doing? > > > indeed this looks suspect. Is this an SMP system? > > Ingo > Actually no. It is an SMP ready system, but with a single PII 450. As I responded to Lee's response, I am not sure that I completely trust the results of this trace anyway. I would like to know why you guys think this may be a false positive. Is it just the extremely long latency? Or is there something else that makes it look suspect? By the way I just posted two more traces, one that I caught last night and one from this morning: This is another one similar to the last but much more reasonably latency: http://www.cybsft.com/testresults/2.6.8.1-P7/2.6.8.1-P7-1.txt And this one this morning appears to be from updatedb running, while the tests were running. It's worth noting that this one appears to have happened about the same time today that the other ~4100+ one happened yesterday. Also worth noting is that the system was probably swapping pretty good when this occurred. http://www.cybsft.com/testresults/2.6.8.1-P7/2.6.8.1-P7-2.txt kr