From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762523AbXGWG4x (ORCPT ); Mon, 23 Jul 2007 02:56:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757340AbXGWG4o (ORCPT ); Mon, 23 Jul 2007 02:56:44 -0400 Received: from mga01.intel.com ([192.55.52.88]:55412 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753872AbXGWG4o (ORCPT ); Mon, 23 Jul 2007 02:56:44 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.16,569,1175497200"; d="scan'208";a="271462841" Subject: [RFC 0/8]KVM: swap out guest pages From: Shaohua Li To: kvm-devel , lkml Cc: Avi Kivity , Ingo Molnar Content-Type: text/plain Date: Mon, 23 Jul 2007 14:51:29 +0800 Message-Id: <1185173489.2645.64.camel@sli10-conroe.sh.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 (2.8.3-2.fc6) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This patch series make kvm guest pages be able to be swapped out and dynamically allocated. Without it, all guest memory is allocated at guest start time. patches are against latest git, and you need first patch Avi's kvm-sch integration patch (http://sourceforge.net/mailarchive/forum.php?thread_name=11841693332609-git-send-email-avi%40qumranet.com&forum_name=kvm-devel ). Patch is quite stable in my test. With the patch, I can run a 256M memory guest in a 300M memory host. If guest is idle, the memory it used can be less than 10M. I did a simple performance test (measure kernel build time in guest), if there is few swap, the performance w/wo the patch difference isn't significent. If you have better measurement approach, please let me try. Unresolved issue: 1. swapoff doesn't work, we need a hook. 2. SMP guest might not work, as kvm doesn't support smp till now. 3. better algorithm to select swaped out guest pages according to guest's memory usage. Maybe more. Any suggests and comments are appreciated. Thanks, Shaohua