Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932107AbVIRQDA (ORCPT ); Sun, 18 Sep 2005 12:03:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932108AbVIRQDA (ORCPT ); Sun, 18 Sep 2005 12:03:00 -0400 Received: from 167.imtp.Ilyichevsk.Odessa.UA ([195.66.192.167]:22154 "HELO port.imtp.ilyichevsk.odessa.ua") by vger.kernel.org with SMTP id S932107AbVIRQC7 (ORCPT ); Sun, 18 Sep 2005 12:02:59 -0400 From: Denis Vlasenko To: Al Boldi Subject: Re: Eradic disk access during reads Date: Sun, 18 Sep 2005 19:02:17 +0300 User-Agent: KMail/1.8.2 Cc: Willy Tarreau , linux-kernel@vger.kernel.org References: <200509170717.03439.a1426z@gawab.com> <200509181400.27004.vda@ilport.com.ua> <200509181640.19984.a1426z@gawab.com> In-Reply-To: <200509181640.19984.a1426z@gawab.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200509181902.17633.vda@ilport.com.ua> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1920 Lines: 50 > > > > # dd if=/dev/hda of=/dev/null bs=16M > > > 2.4.31 # nmeter t6 c x i b d100 > > > 18:56:36.009981 cpu [SSSSSSSS..] ctx 145 int 86 bio 4.7M 0 > > > 18:56:36.110327 cpu [SSSSSSSS..] ctx 145 int 87 bio 4.8M 0 > > > 18:56:36.210735 cpu [SSSSSSSS..] ctx 139 int 88 bio 4.7M 0 > > > 18:56:36.310315 cpu [SSSSSSSS..] ctx 142 int 85 bio 4.7M 0 > > > > > > 2.6.13 # nmeter t6 c x i b d100 > > > 18:09:22.117959 cpu [SSSSSSSSSD] ctx 80 int 47 bio 4.7M 0 > > > 18:09:22.217932 cpu [SSSSSSDDDD] ctx 83 int 48 bio 4.8M 0 > > > 18:09:22.319200 cpu [SSSSDDDDDI] ctx 81 int 56 bio 4.7M 28k > > > 18:09:22.407979 cpu [SSSSSSSSSD] ctx 60 int 38 bio 3.8M 0 > > > 18:09:22.517960 cpu [SSSSSSSSDI] ctx 95 int 61 bio 5.2M 52k > > > > Well, I do not see any bursts you mention... > > Can you try 2.4.31? Not easy. I guess I have quite a few 2.6-only things here... > same here. > > > My CPU is not that new: > > PII - 400Mhz here. I meant that kernel seem to eat too much CPU here. This is not expected. I expected CPU bar to be all D. > > hdc (an old disk): > > 13:52:40.201718 cpu [SSSDDDDDDD] ctx 26 int 112 bio 1.2M 0 > > 13:52:40.301569 cpu [SSDDDDDDDD] ctx 28 int 109 bio 1.2M 0 > > 13:52:40.402552 cpu [SSDDDDDDDI] ctx 23 int 111 bio 1.2M 0 > > 13:52:40.502535 cpu [SSDDDDDDDD] ctx 22 int 110 bio 1.2M 0 > > 13:52:40.601507 cpu [SSDDDDDDDI] ctx 26 int 111 bio 1.2M 0 > > 13:52:40.701493 cpu [SSDDDDDDDD] ctx 23 int 110 bio 1.2M 0 > > Looks smooth. > > Also, great meter! Best of all does not hog the CPU! > Could you add a top3 procs display? What is a "top3 procs display"? -- vda - 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/