From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Gross Subject: Migration with linear p2m list Date: Thu, 3 Dec 2015 08:41:39 +0100 Message-ID: <565FF233.5040302@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: "xen-devel@lists.xen.org" , Andrew Cooper List-Id: xen-devel@lists.xenproject.org I'm just working on a patch series to support migration via using the virtual mapped linear p2m list. Migration seems to work quite nice and now I'm looking into how to support changes of the p2m list structure during migration. For this purpose we introduced p2m_generation in the shared info structure which is incremented by the guest in case of changing a mapping of the p2m list. The question is: what kind of support should I add initially: 1) none: same as for the p2m tree used today 2) minimal: detect a change and cancel migration in this case 3) medium: detect a change and restart migration (limited by a retry count) 4) full: detect a change and adapt the current migration to it (remap p2m list, resend it to receive side, adapt logdirty map) As such a change should be rare I'm currently heading for the minimal solution. Full support could be added later independent from the initial p2m list support. Any thoughts? Juergen