From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rik van Riel Subject: Re: [PATCH 2/9] Sched clock paravirt op fix.patch Date: Tue, 13 Mar 2007 12:37:53 -0400 Message-ID: <45F6D361.8080106@redhat.com> References: <200703020254.l222sOaM009656@zach-dev.vmware.com> <20070313140129.GB92373@muc.de> <45F6C2A3.4040305@goop.org> <20070313160709.GH10574@sequoia.sous-sol.org> <20070313161656.GA12128@muc.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20070313161656.GA12128@muc.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.osdl.org Errors-To: virtualization-bounces@lists.osdl.org To: Andi Kleen Cc: Chris Wright , Andrew Morton , Linus Torvalds , Daniel Walker , Virtualization Mailing List , Linux Kernel Mailing List List-Id: virtualization@lists.linuxfoundation.org Andi Kleen wrote: > On Tue, Mar 13, 2007 at 09:07:09AM -0700, Chris Wright wrote: >> * Jeremy Fitzhardinge (jeremy@goop.org) wrote: >>> In other words, regardless of whether this particular pv_op lives or >>> dies, we're going to need to have to deal with stolen time properly. I >>> think this hook is reasonable and useful step towards doing that. >> Exactly. Normal interrupts we can handle. Having CPU completely >> disappear for unkown time periods we can't, and will need to. > = > But that is just what a interrupt is. Interrupts tend to be reasonably short though. Steal time can be several hypervisor/host time slices long. As an aside, normal interrupts *are* accounted for separately in /proc/stat, so why not steal time too? -- = Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030768AbXCMQjx (ORCPT ); Tue, 13 Mar 2007 12:39:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030773AbXCMQjx (ORCPT ); Tue, 13 Mar 2007 12:39:53 -0400 Received: from mx1.redhat.com ([66.187.233.31]:59454 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030768AbXCMQjx (ORCPT ); Tue, 13 Mar 2007 12:39:53 -0400 Message-ID: <45F6D361.8080106@redhat.com> Date: Tue, 13 Mar 2007 12:37:53 -0400 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Thunderbird 1.5.0.7 (X11/20061008) MIME-Version: 1.0 To: Andi Kleen CC: Chris Wright , Andrew Morton , Daniel Walker , Virtualization Mailing List , Linux Kernel Mailing List , Linus Torvalds Subject: Re: [PATCH 2/9] Sched clock paravirt op fix.patch References: <200703020254.l222sOaM009656@zach-dev.vmware.com> <20070313140129.GB92373@muc.de> <45F6C2A3.4040305@goop.org> <20070313160709.GH10574@sequoia.sous-sol.org> <20070313161656.GA12128@muc.de> In-Reply-To: <20070313161656.GA12128@muc.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andi Kleen wrote: > On Tue, Mar 13, 2007 at 09:07:09AM -0700, Chris Wright wrote: >> * Jeremy Fitzhardinge (jeremy@goop.org) wrote: >>> In other words, regardless of whether this particular pv_op lives or >>> dies, we're going to need to have to deal with stolen time properly. I >>> think this hook is reasonable and useful step towards doing that. >> Exactly. Normal interrupts we can handle. Having CPU completely >> disappear for unkown time periods we can't, and will need to. > > But that is just what a interrupt is. Interrupts tend to be reasonably short though. Steal time can be several hypervisor/host time slices long. As an aside, normal interrupts *are* accounted for separately in /proc/stat, so why not steal time too? -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic.