Re: Running PV kernel on XenServer kills all VMs

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Tue, Jun 15, 2010 at 03:13:08PM +0100, Stephen Borrill wrote:
> I spoke to Citrix about this problem. They said:
> 
> "These messages can only occur with a network front end which uses
> "flipping" mode for RX traffic. We currently do not support (and
> therefore do not test) any guests which use this mode and it looks like
> it has repressed.
> 
> Someone needs to port the BSD frontend to use "copying" mode for its RX
> traffic. Flipping mode may well disappear in a future release."

I'd say this is a regression. flipping mode should be a bit faster
for TCP (it was in my benchmarks at last, on a UP system).
Now, copying mode shouldn't be hard to add, we already support it in the
backend. We just need to see in a linux driver what this means for the
frontend ...

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--