From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 3 May 2001 23:10:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 3 May 2001 23:10:04 -0400 Received: from penguin.e-mind.com ([195.223.140.120]:15702 "EHLO penguin.e-mind.com") by vger.kernel.org with ESMTP id ; Thu, 3 May 2001 23:09:52 -0400 Date: Fri, 4 May 2001 05:09:33 +0200 From: Andrea Arcangeli To: Jeffrey Kuskin Cc: linux-kernel@vger.kernel.org Subject: Re: 2.4.4+fork patch still sluggish Message-ID: <20010504050933.B1902@athlon.random> In-Reply-To: <15090.2067.861480.564724@byte.users.atheros.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <15090.2067.861480.564724@byte.users.atheros.com>; from jsk@atheros.com on Thu, May 03, 2001 at 06:38:27PM -0700 X-GnuPG-Key-URL: http://e-mind.com/~andrea/aa.gnupg.asc X-PGP-Key-URL: http://e-mind.com/~andrea/aa.asc Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 03, 2001 at 06:38:27PM -0700, Jeffrey Kuskin wrote: > This is basically a followup to the "2.4.4 sluggish under fork load" > thread. > > I am using Redhat 7.1 on a 128MB 400 MHz PII system. I have a > locally-built 2.4.4 kernel to which I manually applied the patch that backs > out the child-before-parent behavior on a fork. Namely, this patch: > > > > However, even with this patch applied, I still see extremley jerky mouse > pointer behavior when I run any kind of job that does lots of forking. For > example, a kernel compile or even just the "configure" in preparation for > compiling XEmacs. > > The same behavior, on exactly the same machine, did _not_ occur with Redhat > 6.2/kernel 2.2.19. > > I see that this patch has recently been merged into 2.4.5-pre1, but I am > concerned that it does actually fix the underlying problem. > > Do others continue to see "jerky mouse pointer" behavior even with this > patch installed, or should I look for other causes? For instance, are > there known problems with jerky mouse pointer behavior under heavy swapping > load? That's a bug in the get-child-timeslice logic that I mentioned a few days ago. Interesting strict fixes for this issue are here (they won't apply cleanly to 2.4.5pre1 but fixing reject is trivial): ftp://ftp.us.kernel.org/pub/linux/kernel/people/andrea/kernels/v2.4/2.4.5pre1aa1/10_parent-timeslice-6 ftp://ftp.us.kernel.org/pub/linux/kernel/people/andrea/kernels/v2.4/2.4.5pre1aa1/20_share-timeslice-2 If you can reproduce on 2.4.5pre1aa1 let us know. Thanks! Andrea