Using VirtualGL with the VGL Transport

Advantages/Disadvantages of the VGL Transport

Advantages

• Every application window appears as a separate window on the user’s desktop.
• consumes fewer server resources, since the 2D (X11) rendering occurs on the client machine
• supports stereographic and overlay rendering

Disadvantages

• The VGL Transport relies on the chatty remote X11 protocol.
  As a result, the VGL Transport is not recommended for use on high-latency or low-bandwidth networks.
• As with any remote X11 app, if the network connection drops, then the application will exit.

Using VirtualGL with the VGL Transport requires four general steps.

1. Install VirtualGL on your local machine.
2. Start an X Server on your local machine.
3. Connect to JURECAVIS with vglconnect -s.
4. Start the application with vglrun.

1. Install VirtualGL …

Before you use can call vglconnect -s <userid>@jurecavis.fz-juelich.de you have to install VirtualGL on your local machine:

• Linux/MacOSX - ​http://www.virtualgl.org
• Windows+Cygwin - ​http://www.virtualgl.org/vgldoc/2_2/#hd004005
• Windows+Exceed - ​http://www.virtualgl.org/vgldoc/2_2/#hd004004

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2. Start an X Server …

Start an X Server on your local machine.

• Linux
  • your X11 server is used for your standard desktop and should be running already
• MacOSX
  • start the Mac X11 application
  • in the X11 application, start a new xterm [Command-N] if one isn’t already started
• Windows\Cygwin
  • start Cygwin/X
  • start a new xterm if one isn’t already started (right-click on the Cygwin/X taskbar icon, then select Applications–>xterm.)

3. Connect to JURECAVIS …

In this scenario any OpenGL commands are computed to a JPEG on JURECAVIS and send to the local machine via the VGL Transport Layer. The 2D (X11) command are directly passed to the local X server running on your machine. By default the X11 traffic is encrypted, but the VGL Transport is left unencrypted to maximize performance. This will fail on JURECA - you need to encrypt the VGL Transport, too, which is forced with the -s flag:

vglconnect -s <USERID>@jurecavis.fz-juelich.de

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4. Start the application …

Now start your application on JURECA with vglrun:

vglrun <APP>

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