Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 15 Mar 2002 01:37:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 15 Mar 2002 01:36:59 -0500 Received: from syr-24-24-11-40.twcny.rr.com ([24.24.11.40]:16632 "EHLO server.foo") by vger.kernel.org with ESMTP id ; Fri, 15 Mar 2002 01:36:54 -0500 Date: Fri, 15 Mar 2002 01:36:44 -0500 From: Dan Maas To: linux-kernel@vger.kernel.org Subject: unwanted disk access by the kernel? Message-ID: <20020315013644.A26891@morpheus> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i X-Info: http://www.dcine.com Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I've been trying to set up my laptop for mobile use. I'm having a problem with unwanted disk activity - even when the system is completely idle, there is still an occasional trickle of disk writes (which prevents the poor hard drive from ever spinning down). Yes, I thought this was a user-space issue too - but even booting into a bare-bones root environment does not stop the occasional disk access! Here is everything that's left: PID USER VSZ RSS TIME STAT COMMAND WCHAN 7 root 0 0 00:00:00 SW [kupdated] kupdate 6 root 0 0 00:00:00 SW [bdflush] bdflush 5 root 0 0 00:00:00 SW [kswapd] kswapd 4 root 0 0 00:00:00 SWN [ksoftirqd_CPU0] ksoftirqd 1 root 1316 524 00:00:05 S init [S] select 2 root 0 0 00:00:00 SW [keventd] context_thread 3 root 0 0 00:00:00 SW [kapmd] apm_mainloop 8 root 0 0 00:00:00 Z [khubd exit 879 root 1316 524 00:00:00 S init [S] wait4 880 root 2556 1576 00:00:00 S \_ bash wait4 927 root 3524 1512 00:00:00 R \_ ps afx - - If I manually spin down the disk, it always wakes up within 30 seconds or so. During the spin-up, kupdated goes into the 'D' state and blocks in wait_on_buffer(). This means it's writing dirty filesystem buffers, right? So who is doing the dirtying? I've eliminated all possible user-space sources of I/O! (strace confirms that NO user-space processes are doing I/O; they're all sleeping...) (I'm running a stock Linus 2.4.18 kernel, with APM enabled. The system is Debian woody. All filesystems are ext2.) Regards, Dan - 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/