Re: [VirtualGL-Users] Single application runs very slow withVirtualGL/TurboVNC while others run fine

[DRC <dco...@us...>]

> Btw. what is worse, high latency (6-8ms) or limited bandwidth 
> regarding smooth 
> display?

There are really two aspects to the performance of an app running in VGL --
there is the 3D performance, and there is the 2D performance.  VirtualGL
redirects the 3D so that you don't have to send 3D commands over the
network, but it doesn't do anything to the 2D commands.  So if you're
running with a remote X server and VGLclient, then the 2D commands are still
being sent over the network to your client machine as they would be if you
just ran the app in a normal remote X environment.  So, depending on how the
app is written, even 6-8ms of latency may cause the GUI to be slow.
However, the 3D interaction should still be sufficiently fast.  You
shouldn't notice a significant fall-off in 3D performance until around 50ms.

In any case, if you are discovering that the application GUI is performing
slowly, then the solution is to use TurboVNC.  TurboVNC renders the X11
commands on the server and sends only images over to the client machine.


> For example if the display lags, it is difficult to precisely 
> move objects 
> with the mouse. With lots of lags the object still rotates 
> when the mouse 
> input stopped. So the users need to undo wiggly movements.

The frame spoiling feature in VirtualGL is designed to mitigate this effect
somewhat.