Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932244AbXBPLDM (ORCPT ); Fri, 16 Feb 2007 06:03:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932272AbXBPLDM (ORCPT ); Fri, 16 Feb 2007 06:03:12 -0500 Received: from 207.47.60.150.static.nextweb.net ([207.47.60.150]:19379 "EHLO webmail.xensource.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932244AbXBPLDL (ORCPT ); Fri, 16 Feb 2007 06:03:11 -0500 User-Agent: Microsoft-Entourage/11.2.5.060620 Date: Fri, 16 Feb 2007 11:03:06 +0000 Subject: Re: [patch 14/21] Xen-paravirt: Add XEN config options and disableunsupported config options. From: Keir Fraser To: Andrew Morton , Keir Fraser CC: Chris Wright , Andi Kleen , , Ian Pratt , , Steven Hand , Christian Limpach , Message-ID: Thread-Topic: [patch 14/21] Xen-paravirt: Add XEN config options and disableunsupported config options. Thread-Index: AcdRugj+R6aSPL2tEduvqQAX8io7RQ== In-Reply-To: <20070216025452.d25e3545.akpm@linux-foundation.org> Mime-version: 1.0 Content-type: text/plain; charset="US-ASCII" Content-transfer-encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1108 Lines: 26 On 16/2/07 10:54, "Andrew Morton" wrote: > OK, you're screwed. I agree that the process freezer is the way out of that > one. > > Ingo said that he's clocked the freezer at a few milliseconds. But if it's > any higher than that it'll need to get sped up once we convert cpu hotplug > to use it. A few milliseconds is acceptable. Presumably that is under some stress workload? What we'd really like is to be able to gang-hotplug CPUs to amortise the freezer overhead. This initial patchset does not include save/restore support anyway, so in fact it would be consistent to have CONFIG_PREEMPT configurable. I'm sure that we are going to have some nasty bugs to fix up as a result, but we can't fix them until we find them! Then we can convert our save/restore code to use the freezer before submitting it for inclusion. -- Keir - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/