From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762859AbXLQPcj (ORCPT ); Mon, 17 Dec 2007 10:32:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754883AbXLQPcb (ORCPT ); Mon, 17 Dec 2007 10:32:31 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.31.123]:40838 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754512AbXLQPcb (ORCPT ); Mon, 17 Dec 2007 10:32:31 -0500 Date: Mon, 17 Dec 2007 16:32:29 +0100 From: Jan Kara To: Denis Cc: linux-kernel@vger.kernel.org Subject: Re: Fwd: NFS , Kjournald - status D (uninterruptible sleep) - maquina lenta. Message-ID: <20071217153228.GC6979@atrey.karlin.mff.cuni.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Dears, I've got a double dual xeon wich sometimes is getting too slow. > > > While i was observing one of these slowly times, I realized the time > wait of processors come close to 100% and nfsd and kjournald process > become to D status (uniterruptible sleep) .Does someone know why this > can be happening or how can I troubleshoot it? > > Below is a 'draw' of my top at one of these moments. > > [root@cromo src]# top > top - 10:59:02 up 6 days, 19:30, 17 users, load average: 14.77, 13.46, 13.00 > Tasks: 189 total, 1 running, 188 sleeping, 0 stopped, 0 zombie > Cpu0 : 0.0% us, 0.4% sy, 0.0% ni, 0.2% id, 98.5% wa, 0.0% hi, 0.9% si > Cpu1 : 0.0% us, 0.4% sy, 0.0% ni, 0.0% id, 99.6% wa, 0.0% hi, 0.0% si > Cpu2 : 0.0% us, 0.2% sy, 0.0% ni, 7.8% id, 92.0% wa, 0.0% hi, 0.0% si > Cpu3 : 0.2% us, 0.8% sy, 0.0% ni, 0.0% id, 98.7% wa, 0.2% hi, 0.0% si All processors are in iowait - i.e. waiting for IO. > Mem: 4025540k total, 4018264k used, 7276k free, 7908k buffers > Swap: 4096564k total, 3288k used, 4093276k free, 3553252k cached > > 3941 root 15 0 0 0 0 D 2 0.0 80:29.30 nfsd > 3938 root 15 0 0 0 0 D 1 0.0 81:02.02 nfsd > 2459 root 15 0 0 0 0 D 1 0.0 30:57.04 kjournald > 3937 root 15 0 0 0 0 D 1 0.0 82:07.99 nfsd > 96 root 15 0 0 0 0 S 0 0.0 34:12.48 kswapd0 > 3940 root 15 0 0 0 0 D 0 0.0 80:22.55 nfsd > 3942 root 15 0 0 0 0 D 0 0.0 80:23.66 nfsd > 3939 root 15 0 0 0 0 D 0 0.0 82:22.55 nfsd It seems like heavy disk/network activity. You can try running vmstat 1 It will print every second the situation of your memory / IO subsystem. You should especially see the ---io--- column ('bi' means blocks in, 'bo' blocks outputted). I guess they'd contain some non-trivial values... BTW: I guess the processes wake up eventually, don't they? Honza -- Jan Kara SuSE CR Labs