From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754729AbYICM2y (ORCPT ); Wed, 3 Sep 2008 08:28:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751528AbYICM2p (ORCPT ); Wed, 3 Sep 2008 08:28:45 -0400 Received: from mtagate2.uk.ibm.com ([194.196.100.162]:35332 "EHLO mtagate2.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751317AbYICM2p (ORCPT ); Wed, 3 Sep 2008 08:28:45 -0400 Message-ID: <48BE82F9.4020808@fr.ibm.com> Date: Wed, 03 Sep 2008 14:28:41 +0200 From: Cedric Le Goater User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Andrey Mirkin CC: linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org Subject: Re: [PATCH 0/9] OpenVZ kernel based checkpointing/restart References: <1220439476-16465-1-git-send-email-major@openvz.org> In-Reply-To: <1220439476-16465-1-git-send-email-major@openvz.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andrey Mirkin wrote: > This patchset introduces kernel based checkpointing/restart as it is > implemented in OpenVZ project. This patchset has limited functionality and > are able to checkpoint/restart only single process. Recently Oren Laaden > sent another kernel based implementation of checkpoint/restart. The main > differences between this patchset and Oren's patchset are: > > * In this patchset checkpointing initiated not from the process > (right now we do not have a container, only namespaces), Oren's patchset > performs checkpointing from the process context. > > * Restart in this patchset is initiated from process, which restarts a new > process (in new namespaces) with saved state. Oren's patchset uses the same > process from which restart was initiated and restore saved state over it. > > * Checkpoint/restart functionality in this patchset is implemented as a kernel > module why ? Do we really think that C/R implementations will be so different that we will need C/R ops to support all of them ? I imagine that there could be different models : 1. brute force : dump it all and kill 2. incremental 3. live migration ... But I see all of them really tied to the kernel internals. The first issues I see with this direction are some EXPORT_SYMBOL() that would be useless without a module. > As checkpointing is initiated not from the process which state should be saved > we should freeze a process before saving its state. Right now Container Freezer > from Matt Helsley can be used for this. OK that's integrated and Daniel's tools : http://lxc.cvs.sourceforge.net/lxc/ one more reason to work on integration :) C. > This patchset introduce only a concept how kernel based checkpointing/restart > can be implemented and are able to checkpoint/restart only a single process > with simple VMAs. > > I've tried to split my patchset in small patches to make review more easier. > _______________________________________________ > Containers mailing list > Containers@lists.linux-foundation.org > https://lists.linux-foundation.org/mailman/listinfo/containers >