Aim: to launch a parallel job on the CHPC cluster Lengau.
The slides for the OpenMP lecture on Linux will be posted.
Download and install putty-ssh and connect to
lengau.chpc.ac.za using the username (studentNN) and password provided.
Documentation for the CHPC systems starts with the CHPC Quick Start Guide. Read it, but note the differences below which are specific to the
studentNN accounts you are using.
A user can not simply ssh onto a compute node because you don't know which ones are not in use by a currently running job. But the PBSPro scheduler does know. So we ask the scheduler for an interactive job which gives us a login shell on a compute node:
qsub -I -P Wchpc -q R522145 -W group_list=training
-Iselects an interactive job
If you find your interactive session timing out too soon then add
-l walltime=4:0:0 to the above command line to request the maximum 4 hours.
To carry out the exercises in the first OpenMP practical you must run the examples on a compute node and not the login node.
After logging on to lengau, the first thing you will do is request an interactive session on a compute node:
qsub -I -P Wchpc
Your prompt will change to something like:
Remember, this is a login shell so you can change the environment as before, for example, change the prompt with
export PS1='\h:\w\$ '
and now see
Download and follow the worksheet.
Copy the OpenMP_Tut.tar.gz file from the student00 home directory to your home directory.
cp ~/../student00/OpenMP_Tut.tar.gz ~/lustre cd ~/lustre
Then untar (unpack) it.
tar -zxvf OpenMP_Tut.tar.gz
And then go into the OpenMP/ tut directory and start the practical. Have fun!
Most of the prac can be done in an interactive session.