[Spice-devel] hardcoded NUM_DRAWABLES too small

[Dietmar Maurer]

> > No. There is no need to draw anything at the server side (for spiceterm).
> 
> Ok, that would be interesting. I wonder if you are not better off implementing a
> new display channel for your use case, if you just need to send off your own
> rendering commands without any change.

why is that better? I just want to disable local rendering.
 
> > > Isnt't the 1000 drawables limit just slowing down the caller
> > > (guest/vm side), to leave time for clients to process all drawables
> > > in the pipes.
> >
> > no, it leads to additional draw commands on the server side. So this
> > is a waste of computing power.
> >
> > > What alternative do you propose?
> >
> > NUM_DRAWABLES=3000
> 
> Explain 3000? What if tomorrow you need a bigger terminal? We will need to
> change it again.

The number of character cells inside a terminal window is about 80x25 ==> 2000, so
it is likely that a value of 1000 is not enough.

==> bigger is better for this particular problem

> > but I guess that can have a negative performance impact elsewhere?
> 
> Mostly on memory consumption, but also probably on some other area, like
> latency or cpu usage.
> 
> > > > I guess one would see the same effect when running a xterm inside
> > > > a VM, because
> > > >
> > > > a terminal has a size of 80x25 characters, which gives 2000
> > > > different regions.
> > > >
> > > >
> > > >
> > > > What is the suggested way to avoid such things?
> > >
> > > I'll let someone else reply suggestion, as I don't know myself.
> > >
> > > > Also, I don’t think I need the rendered content on the server side
> > > > for spiceterm (why?).
> > >
> > > > So is it possible to disable server side rendering at all?
> > >
> > > If you don't have client connected or for reconnection, you still
> > > want complete rendering ready, no?
> >
> > No, I do not really need that. spiceterm only allows a single connection.
> 
> Ok, but even for the first connection, you want to be shown with the current
> content, don't you?

no - the application itself knows how to redraw.