From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: Domain Save Image Format proposal (draft B) Date: Mon, 10 Feb 2014 17:32:34 +0000 Message-ID: <52F90D32.7080807@citrix.com> References: <52F90A71.40802@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <52F90A71.40802@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: David Vrabel Cc: Shriram Rajagopalan , Stefano Stabellini , Ian Jackson , Ian Campbell , "Xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org On 10/02/14 17:20, David Vrabel wrote: > Here is a draft of a proposal for a new domain save image format. It > does not currently cover all use cases (e.g., images for HVM guest are > not considered). > > http://xenbits.xen.org/people/dvrabel/domain-save-format-B.pdf > > Introduction > ============ > > Revision History > ---------------- > > -------------------------------------------------------------------- > Version Date Changes > ------- ----------- ---------------------------------------------- > Draft A 6 Feb 2014 Initial draft. > > Draft B 10 Feb 2014 Corrected image header field widths. > > Minor updates and clarifications. > -------------------------------------------------------------------- > > Purpose > ------- > > The _domain save image_ is the context of a running domain used for > snapshots of a domain or for transferring domains between hosts during > migration. > > There are a number of problems with the format of the domain save > image used in Xen 4.4 and earlier (the _legacy format_). > > * Dependant on toolstack word size. A number of fields within the > image are native types such as `unsigned long` which have different > sizes between 32-bit and 64-bit hosts. This prevents domains from > being migrated between 32-bit and 64-bit hosts. s/hosts/toolstacks/ (or toolstack domains) ~Andrew