From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756021AbXJ3RZr (ORCPT ); Tue, 30 Oct 2007 13:25:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752489AbXJ3RZi (ORCPT ); Tue, 30 Oct 2007 13:25:38 -0400 Received: from gw.goop.org ([64.81.55.164]:47896 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752963AbXJ3RZi (ORCPT ); Tue, 30 Oct 2007 13:25:38 -0400 Message-ID: <4727690F.4030502@goop.org> Date: Tue, 30 Oct 2007 10:25:35 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.5 (X11/20070727) MIME-Version: 1.0 To: tgh CC: Jeremy Fitzhardinge , Xen-devel , Andi Kleen , lkml , Chris Wright , Andrew Morton Subject: Re: [Xen-devel] [patch 30/44] xen: Add support for preemption References: <20070716231536.937393000@xensource.com>> <20070716232915.672717000@xensource.com>> <4726F51C.4030709@sina.com.cn> In-Reply-To: <4726F51C.4030709@sina.com.cn> X-Enigmail-Version: 0.95.4 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org tgh wrote: > hi > I am using xen,and I am curious about whether Xen support the preempt > scheduler for the VMs or not > could the VM be prempted by xen to scheduler another VM? > Yes, that's the normal mode of operation. The hypervisor will timeslice multiple vcpus onto a single vcpu. This patch doesn't relate to that; it's whether a Xen Linux guest's kernel can be preempted to reschedule processes while running under Xen. The normal xen-unstable or vendor Xen kernels don't support this, but the mainline kernel with paravirt_ops/xen support does. J