Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754663AbcCJJai (ORCPT ); Thu, 10 Mar 2016 04:30:38 -0500 Received: from mx2.parallels.com ([199.115.105.18]:53455 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752894AbcCJJa2 (ORCPT ); Thu, 10 Mar 2016 04:30:28 -0500 Date: Thu, 10 Mar 2016 12:30:08 +0300 From: Roman Kagan To: Rik van Riel CC: "Michael S. Tsirkin" , "Li, Liang Z" , "Dr. David Alan Gilbert" , "ehabkost@redhat.com" , "kvm@vger.kernel.org" , "quintela@redhat.com" , "linux-kernel@vger.kernel.org" , "qemu-devel@nongnu.org" , "linux-mm@kvack.org" , "amit.shah@redhat.com" , "pbonzini@redhat.com" , "akpm@linux-foundation.org" , "virtualization@lists.linux-foundation.org" , "rth@twiddle.net" Subject: Re: [Qemu-devel] [RFC qemu 0/4] A PV solution for live migration optimization Message-ID: <20160310093007.GA14065@rkaganb.sw.ru> Mail-Followup-To: Roman Kagan , Rik van Riel , "Michael S. Tsirkin" , "Li, Liang Z" , "Dr. David Alan Gilbert" , "ehabkost@redhat.com" , "kvm@vger.kernel.org" , "quintela@redhat.com" , "linux-kernel@vger.kernel.org" , "qemu-devel@nongnu.org" , "linux-mm@kvack.org" , "amit.shah@redhat.com" , "pbonzini@redhat.com" , "akpm@linux-foundation.org" , "virtualization@lists.linux-foundation.org" , "rth@twiddle.net" References: <20160304163246-mutt-send-email-mst@redhat.com> <20160305214748-mutt-send-email-mst@redhat.com> <20160307110852-mutt-send-email-mst@redhat.com> <20160309142851.GA9715@rkaganb.sw.ru> <20160309173017-mutt-send-email-mst@redhat.com> <20160309170438.GB9715@rkaganb.sw.ru> <1457552332.17933.24.camel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <1457552332.17933.24.camel@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-ClientProxiedBy: US-EXCH.sw.swsoft.com (10.255.249.47) To US-EXCH2.sw.swsoft.com (10.255.249.46) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1139 Lines: 30 On Wed, Mar 09, 2016 at 02:38:52PM -0500, Rik van Riel wrote: > On Wed, 2016-03-09 at 20:04 +0300, Roman Kagan wrote: > > On Wed, Mar 09, 2016 at 05:41:39PM +0200, Michael S. Tsirkin wrote: > > > On Wed, Mar 09, 2016 at 05:28:54PM +0300, Roman Kagan wrote: > > > > For (1) I've been trying to make a point that skipping clean > > > > pages is > > > > much more likely to result in noticable benefit than free pages > > > > only. > > > > > > I guess when you say clean you mean zero? > > > > No I meant clean, i.e. those that could be evicted from RAM without > > causing I/O. > > > > Programs in the guest may have that memory mmapped. > This could include things like libraries and executables. > > How do you deal with the guest page cache containing > references to now non-existent memory? > > How do you re-populate the memory on the destination > host? I guess the confusion is due to the context I stripped from the previous messages... Actually I've been talking about doing full-fledged balloon inflation before the migration, so, when it's deflated the guest will fault in that data from the filesystem as usual. Roman.