From mboxrd@z Thu Jan 1 00:00:00 1970 From: tgh Subject: Re: [PATCH] (resent) NUMA node migration Date: Sat, 22 Dec 2007 17:42:01 +0800 Message-ID: <476CDBE9.8000507@sina.com.cn> References: <476C40BE.1030907@amd.com> <20071222005315.GA11052@totally.trollied.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Ian Pratt Cc: Andre Przywara , xen-devel@lists.xensource.com, John Levon List-Id: xen-devel@lists.xenproject.org hi for PV, is there a fast checkpoint mechanism available ? how does it=20 work , that is ,what paremeters in the common line"xm migration ",or how=20 to invoke it? and how does it work ,say ,fast checkpoint for PV in an=20 incremental way such as live migration, or how to fast checkpoint ? Thanks in advance Ian Pratt =E5=86=99=E9=81=93: > > Doing page migration for HVM guests is easy as you can just stop the > guest, copy a bunch of pages and update the p2m table, flush the shadow > page table cache and all VCPU's TLBs, then resume. Doing it live is a > little tricky as you have to go from MFN's to PTE's which currently > requires a full shadow page table scan. [Though some of the experimenta= l > page sharing patches maintain linked lists of backpointers, and we coul= d > switch to a shadow mode that supports this while doing page migration]=20 > > PV guests are a little more challenging as all references in the > direct-mode page tables need to be updated. We also need to make sure > that the guest isn't holding MFNs outside of pagetables, so we need to > get all the VCPUs into a known state. The best way of handling this is > to use the PV fast checkpoint support to freeze the guest, copy the > =20 > badly located pages, scan and update all pagetables, resume from > checkpoint. This would make a nice little project for someone... > > Ian > > =20 > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > > > =20