Re: [Qemu-devel] [PATCH 5/8] virtio-serial-bus: Add support for buffering guest output, throttling guests

[Anthony Liguori]

On 01/13/2010 11:14 AM, Markus Armbruster wrote:
> Anthony Liguori<address@hidden>  writes:
>
>    
> > On 01/12/2010 01:16 AM, Amit Shah wrote:
> >      
> > > BTW I don't really want this too, I can get rid of it if everyone agrees
> > > we won't support clipboard writes>   4k over vnc or if there's a better
> > > idea.
> > >
> > >        
> > Why bother trying to preserve message boundaries?   I think that's the
> > fundamental question.
> >      
> Yes.  Either it's a datagram or a stream pipe.  I always thought it
> would be a stream pipe, as the name "serial" suggests.
>    

And if it's a datagram, then we should accept that there will be a fixed 
max message size which is pretty common in all datagram protocols.  That 
fixed size should be no larger than what the transport supports so in 
this case, it would be 4k.

If a guest wants to send larger messages, it must build a continuation 
protocol on top of the datagram protocol.

Regards,

Anthony Liguori