[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Checkpointing for HVM guest with PV driver



On Wednesday, 08 September 2010 at 22:36, Jiang, Yunhong wrote:
> Hi, Brendan, I noticed following code in checkpoint_open() in 
> tools/python/xen/lowlevel/checkpoint/libcheckpoint.c:
> 
>     } else if (s->domtype == dt_pvhvm) {
>        checkpoint_close(s);
>        s->errstr = "PV-on-HVM is unsupported";
> 
>        return -1;
>     }
> 
> This check means for HVM guest with PV driver, the checkpoint/remus will not 
> work. Are there any special reason for this checking?
> 
> Originally I thought PV driver on HVM guest can't live migrate, but I did a 
> quick experimental to live migration a HVM guest with PV driver installed, (I 
> only tried to migrate to localhost since I have only one system on hand) and 
> seems it works well, so what's the reason for this restriction?

It simply hasn't been tested. I haven't looked at how suspend
notification/cancellation works in the PVHVM drivers, or whether it
affects ioemu at all. If live migration works already, then there
probably isn't much to it. Have you tried removing that check and
making checkpoint treat PVHVM the same as HVM, then running remus?

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.