From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266388AbUAHU0P (ORCPT ); Thu, 8 Jan 2004 15:26:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266389AbUAHU0P (ORCPT ); Thu, 8 Jan 2004 15:26:15 -0500 Received: from ns.clanhk.org ([69.93.101.154]:40833 "EHLO mail.clanhk.org") by vger.kernel.org with ESMTP id S266388AbUAHU0M (ORCPT ); Thu, 8 Jan 2004 15:26:12 -0500 Message-ID: <3FFD6741.3000300@clanhk.org> Date: Thu, 08 Jan 2004 14:20:49 +0000 From: "J. Ryan Earl" User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031202 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andrew Morton Cc: linux-kernel@vger.kernel.org Subject: Re: Fw: Performance drop 2.6.0-test7 -> 2.6.1-rc2 References: <20040107023042.710ebff3.akpm@osdl.org> <20040107215240.GA768@frodo> <20040108105427.E20265@fi.muni.cz> <20040108021637.15d1b33a.akpm@osdl.org> <20040108112547.G20265@fi.muni.cz> <20040108023356.00db9dec.akpm@osdl.org> In-Reply-To: <20040108023356.00db9dec.akpm@osdl.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: >Jan Kasprzak wrote: > > >>Andrew Morton wrote: >>: Jan Kasprzak wrote: >>: > - this is reliable: repeated boot back to 2.6.1-rc2 makes the problem >>: > appear again (high load, system slow has hell), booting back >>: > to -test7 makes it disappear. >> >> I was about to post something about this as well. I recently went to upgrade a production server in a datacenter. I wanted to use a 2.6 kernel: I tried 2.6.0-mm1 and 2.6.1-rc1-mm1--needed the siimage patches. User space CPU usage was WAY high. I'm talking 2x or more than normal, though sys time was low. Processes that had no connections and should have used 0% CPU were using 1% CPU when no one was even connected. And a loaded process which should only use ~25% CPU was using 60% CPU. Very unresponsive, very slow. I ended up staying with a 2.4.23 kernel with my required patches. I didn't try any other 2.6 kernels, so I can't say which version this problem appeared in, but I DEFINITELY noticed it and it is repeatable. I didn't have time to test further. -ryan