On Tue, May 09, 2006 at 11:26:03PM +1000, Herbert Xu wrote: > Christian Limpach <[EMAIL PROTECTED]> wrote: > > > > Possibly having to page in the process and switching to it would add > > to the live migration time. More importantly, having to install an > > additional program in the guest is certainly not very convenient. > > Sorry I'm still not convinced. What's there to stop me from suspending > my laptop to disk, moving it from port A to port B and resuming it? > > Wouldn't I be in exactly the same situation? By the same reasoning we'd > be adding a gratuitous ARP routine to every single laptop network driver.
It is the same situation except that in the laptop case you don't care that reconfiguring your network will take a second or a few. For live migration we're looking at network downtime from as low as 60ms to something like 210ms on a busy virtual machine. I'm not saying that a userspace solution wouldn't work but it would probably add a measurable delay to the network downtime during live migration. You might also find the following paper an interesting read: http://www.cl.cam.ac.uk/Research/SRG/netos/papers/2005-migration-nsdi-pre.pdf christian - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
