From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42546) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WKSld-0001eQ-0I for qemu-devel@nongnu.org; Mon, 03 Mar 2014 08:18:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WKSlW-0002Aq-G5 for qemu-devel@nongnu.org; Mon, 03 Mar 2014 08:18:48 -0500 Received: from mx1.redhat.com ([209.132.183.28]:14778) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WKSlW-0002Ai-7g for qemu-devel@nongnu.org; Mon, 03 Mar 2014 08:18:42 -0500 Message-ID: <53148124.8040500@redhat.com> Date: Mon, 03 Mar 2014 14:18:28 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <615092B2FD0E7648B6E4B43E029BCFB84D578044@SZXEMA503-MBS.china.huawei.com> <20140303123234.GC21055@stefanha-thinkpad.redhat.com> In-Reply-To: <20140303123234.GC21055@stefanha-thinkpad.redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC]VM live snapshot proposal List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi , "Huangpeng (Peter)" Cc: "kwolf@redhat.com" , Andrea Arcangeli , Pavel Hrdina , Zhanghailiang , KVM devel mailing list , "qemu-devel@nongnu.org" , Dr David Alan Gilbert , Wenchao Xia Il 03/03/2014 13:32, Stefan Hajnoczi ha scritto: > If there is not enough memory to fork, then a synchronous approach to > catching guest memory writes is needed. I'm not sure if a good > mechanism for that exists but the simplest would be mprotect(2) and a > signal handler (which will make the guest run very slowly). I think we'll be adding such a mechanism, but for guest memory reads, for postcopy migration. Perhaps it could be reused for live snapshotting? Paolo