Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262020AbUD1UZy (ORCPT ); Wed, 28 Apr 2004 16:25:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262050AbUD1UYm (ORCPT ); Wed, 28 Apr 2004 16:24:42 -0400 Received: from smtp800.mail.sc5.yahoo.com ([66.163.168.179]:6075 "HELO smtp800.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S262020AbUD1UJS (ORCPT ); Wed, 28 Apr 2004 16:09:18 -0400 Date: Wed, 28 Apr 2004 15:12:49 -0500 (CDT) From: Brent Cook X-X-Sender: busterb@ozma.hauschen Reply-To: busterbcook@yahoo.com To: Andrew Morton cc: linux-kernel@vger.kernel.org Subject: Re: pdflush eating a lot of CPU on heavy NFS I/O In-Reply-To: <20040428124809.418e005d.akpm@osdl.org> Message-ID: References: <20040427230203.1e4693ac.akpm@osdl.org> <20040428124809.418e005d.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2388 Lines: 60 On Wed, 28 Apr 2004, Andrew Morton wrote: > Brent Cook wrote: > > > > On Tue, 27 Apr 2004, Andrew Morton wrote: > > > > > Brent Cook wrote: > > > > > the pdflush process starts using near 100% CPU indefinitely after > > > > a few minutes of initial NFS traffic, as far as I can tell. > > > > > > Please confirm that the problem is observed on the NFS client and not the > > > NFS server? I'll assume the client. > > > > Yes, both affected machines had the issue when connecting as a client to a > > 2.4.25-based NFS server. > > > > > What other filesystems are in use on the client? > > > > One uses Reiser on /, the other uses ext3 on /. Here is the mount table > > for one machine: > > Both machines are exhibiting the problem? Yes. They both exhibit about 5-10 minutes after starting once I start compiling from the NFS share. I'm going to also try a big compile from a local directory to exercise the local FS to eliminate it as a possibility. > > About 10 minutes into the process, pdflush starts taking over: > > > > PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME CPU COMMAND > > 7 root 25 0 0 0 0 RW 34.4 0.0 3:05 0 pdflush > > 17856 busterb 25 0 69400 65M 5140 R 34.4 26.1 0:31 0 cc1plus > > 19466 busterb 25 0 43732 39M 5140 R 26.3 15.5 0:03 0 cc1plus > > ... > > The network light will flash continually on each machine once pdflush > > gets into this state, which makes me think NFS. Each machine has > > 512-256 MB of ram and a single CPU. > > ok.. I spent a couple of hours yesterday trying to get this to happen. No > joy. Can't make it happen with your .config either. I'll set up a 2.4.25 > server later on. > > What version of gcc are you using? 3.3.3 previously. I just did a build with 3.4 with the same results; I'm tracking Slackware-current, so my build environment reflects this. > Could you please capture the contents of /proc/meminfo and /proc/vmstats > when it's happening? Will do. I can also provide a test account to you offline if it helps so you can see it for yourself. - Brent - 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/