From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752619AbYIBJfE (ORCPT ); Tue, 2 Sep 2008 05:35:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751101AbYIBJey (ORCPT ); Tue, 2 Sep 2008 05:34:54 -0400 Received: from wr-out-0506.google.com ([64.233.184.231]:20925 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750953AbYIBJew (ORCPT ); Tue, 2 Sep 2008 05:34:52 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :content-type:content-transfer-encoding:sender; b=E+ldwjtW3PQKiaP7k0v/zIBXtYDXdPacv4Fqubyl/qDKDaiNdBt8UcQCss/6Pzxoky KT26OXDvTIYk+A6DW3DZ+Uzgzufc/ALcoKKt7OOWKN5xugCrhetnDcftm8+dJqEFHkRq Yffk/qMoUcxOQUWJnqYhiM53ePdZMbJBlyLVk= Message-ID: <48BD08B6.4040707@tuffmail.co.uk> Date: Tue, 02 Sep 2008 10:34:46 +0100 From: Alan Jenkins User-Agent: Thunderbird 2.0.0.16 (X11/20080724) MIME-Version: 1.0 To: Jan Knutar CC: jamagallon@ono.com, linux-kernel Subject: Re: Finding what is stuck... Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jan Knutar wrote: > On Tuesday 02 September 2008, J.A. Magallón wrote: > >> I'm running 2.6.27-rc5-git2 on an Aspire One. >> The system is in general pretty responsive, but sometimes it just >> gets totally stuck. Even the mouse stops. >> >> It looks related to disk (SSD) access, but I'm not totally sure. > > Are you hitting swap at all? Does it have swap? > > On my N810 tablet there can be a huge slowdown if it starts swapping. > The first time it dips into swap is relatively painless when stuff gets > written out sequentially, but after that when writes are mostly random > the throughput drops to a few kilobytes per second, causing massive > slowdown... The MMC/SD cards hate random write, and I expect SSDs are > no better. > > iostat -x -k 10 > in a terminal is useful. Check the iowait and util% numbers after/during > slowdown... My experience on the EeePC is similar. I didn't look into it much but I think it helped a lot switching to the "noop" ioscheduler (echo noop > /sys/block/sda/queue/scheduler) as opposed to the default CFQ, if you haven't already done so. Alan