Starter jobs

In this section, a sample job will be provided to give hands-on experience with job submission to the cluster.

Tensor addition sample job

Overview

This job helps to visualise the difference in computational performance for GPU vs CPU.

We will compare the time taken by a GPU vs a CPU, in completing 1 million tensor additions on a 2D matrix.

Download the zip file for this sample here.

Understand the zip file contents

Unzip the downloaded file and open it with a code editor to view the contents.

Add2D.py contains the job code to be ran on the cluster. Use the code comments to help understand the job better

sbatchAdd2D.sh contains the shell script for submitting this job to the cluster

Edit sbatch script

For this sample job, most of the configurations have been pre-set already (Node, Memory, Time, etc.). Refer to the Job submission guide(pip3) and the Shell script generator to find out more about script configuration.

Replace the values in lines 29 - 32 of the script (shown below) with the assigned values:

#SBATCH --partition=student                 # The partition you've been assigned
#SBATCH --account=student   # The account you've been assigned (normally student)
#SBATCH --qos=studentqos       # What is the QOS assigned to you? Check with myinfo command
#SBATCH --mail-user=email@scis.smu.edu.sg # Who should receive the email notifications

Use myinfo command to help determine the assigned partition, account, and qos. Refer to the instructions on Getting your account quota information for more details.

Transfer files onto the cluster

We shall use the SCP to transfer the files onto the cluster.

Open up command prompt and input the following commands, replacing the <> parts with the appropriate filepath and username:

scp <path to Add2D.py file> <username>@origami.smu.edu.sg:~

scp <path to sbatchAdd2D.sh file> <username>@origami.smu.edu.sg:~

The second part of <username>@origami.smu.edu.sg:~ is simply the destination for the file, with ~ signifying the home address of <username>@origami.smu.edu.sg and : being the link.

Submit job to cluster

Run the commands below in sequence to submit the job.

chmod +x sbatchAdd2D.sh

sbatch sbatchAdd2D.sh

The cluster will send an email notification when the job has ended.

Evaluating log

Transfer the job log to your local computer, also using SCP.

scp <username>@origami.smu.edu.sg:~/Add2Dlog.out <destination to save log file>

Read the log and observe the time difference between tensor addition with a CPU, and tensor addition with a GPU. Attached below is a sample log for this job.

Additionally, refer to Job logs for more insights on job script optimization.