From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263385AbTDGLgp (for ); Mon, 7 Apr 2003 07:36:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263386AbTDGLgp (for ); Mon, 7 Apr 2003 07:36:45 -0400 Received: from elixir.e.kth.se ([130.237.48.5]:8203 "EHLO elixir.e.kth.se") by vger.kernel.org with ESMTP id S263385AbTDGLgo (for ); Mon, 7 Apr 2003 07:36:44 -0400 To: Christophe Saout Cc: linux-kernel@vger.kernel.org Subject: Re: An idea for prefetching swapped memory... References: <200304071026.47557.schlicht@uni-mannheim.de> <200304072021.17080.kernel@kolivas.org> <1049715389.1096.7.camel@chtephan.cs.pocnet.net> From: mru@users.sourceforge.net (=?iso-8859-1?q?M=E5ns_Rullg=E5rd?=) Date: 07 Apr 2003 13:48:17 +0200 In-Reply-To: Christophe Saout's message of "07 Apr 2003 13:36:29 +0200" Message-ID: User-Agent: Gnus/5.0807 (Gnus v5.8.7) XEmacs/21.1 (Channel Islands) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Christophe Saout writes: > > > With this feature there should be no performance decrease > > > because only free resources would be used, and if pages were > > > swapped in but not be used, they stay not dirty and so have not > > > to be written to disk when they are swapped out again. But the > > > improvements should be obvious if simply the last swaped out > > > pages are swapped in again... > > > > This has been argued before. Why would the last swapped out pages > > be the best to swap in? The vm subsystem has (somehow) decided > > they're the least likely to be used again so why swap them in? > > Are you sure this is working? When I'm watching a video ofer NFS on > my machine which is idle (just X and mplayer, gnome in background, > 256 MB of memory, 512 swap), after 30 minutes or so, the playback > starts to jump. The cpu usage is below 10%, and it even does this > when both X and mplayer are renice to -19 (!). So the VM swapped > everything out and after 30 minutes it starts to swap out X oder > mplayer itself, which is immediately swapped back in but the video > jumps... :-( How much of your memory is in use? Are you sure there isn't a memory leak somewhere in mplayer? -- Måns Rullgård mru@users.sf.net