How to run GUI applications using GPUs and VNC

If you are interested to start a remote visual session(VNC) on our GPU nodes( for example to launch VMD, Salome, or MOLDEN). Please, read the following instructions:

Steps to start a VNC Session:

As a prerequesite, you need a Linux  Pc and a VNC client.

1. 
   

   1. If is your first time starting a VNC server on CSUC HPC you need to set a vnc passowrd through the following the instructions:
      

      1. Start an interactive session on a GPU node:  

         Start interactive job

         salloc -n 24 -N 1 -p gpu  --gres=gpu:1 -C vnc -t 2:00:00

      2. Run the following commands and follow the screen instructions:

         Start vnc server

         module load tools/turbovnc/2.1.1

         vncserver

      3. When you complete de "wizard" go to step 2.
         
         

   2. If is not your first time starting a VNC server on CSUC HPC: Copy the following script into a slm file and launch it.
      
      

      Start VNC server

      #!/bin/bash
      #SBATCH -p gpu
      #SBATCH -N 1
      #SBATCH -n 24
      #SBATCH --job-name="VNC_server"
      #SBATCH -o vnc_server.out
      #SBATCH -e vnc_server.err
      #SBATCH --gres=gpu:1#

      #SBATCH -C "vnc"
      #SBATCH -t 01:00:00 #1Hour time limit, you can change it as your convenience

      
      module load tools/turbovnc/2.1.1

      vncserver

      sleep 1000000 #Wait until time finishes

2. Download the vnc_tunnel.sh bash scrip and wait until your batch job were on running state.
3. Run  vnc_tunnel.sh on your local machine  and follow the instructions (It is possible that script ask for your CSUC HPC username and password several times during the execution).
4. After the script execution, a ssh tunnel should be created on a local port of your choice. Start your VNC client targeting to "localhost:your_local_port" using the password that you typed the first time you started vncserver (step 1).

NOTICE: Remember to kill your interactive job (scancel JOBID) when you finish the VNC session.

Run GUI apps with GPU acceleration

When you were on a VNC session, you shoud see a KDE Desktop environment. To launch a Xwindows application you should launch a terminal, load the module "tools/virtualgl/2.5" and the module  of your application. After that type: