HPC closing session

  1. Are there any questions on the materials you just watched?
  2. Let’s go together through the challenges, do some exercises, and debug problems.

Click on a triangle to expand a question:

Question 17

Submit a serial job that runs hostname command.

Try playing with sq, squeue, scancel commands.

 
Question 18

Submit a serial job based on pi.c.

Try sstat on a currently running job. Try seff and sacct on a completed job.

 
Question 19 Using a serial job, time optimized (-O2) vs. unoptimized code. Type your findings into the chat.
 
Question 20

Using a serial job, time pi.c vs. pi.py for the same number of terms (cannot be too large or too small – why?).

Python pros – can you speed up pi.py?

 
Question 21 Submit an array job for different values of n (number of terms) with pi.c. How can you have different executable for each job inside the array?
 
Question 22 Submit a shared-memory job based on sharedPi.c. Did you get any speedup? Type your answer into the chat.
 
Question 23

Submit an MPI job based on distributedPi.c.

Try scaling 1 → 2 → 4 → 8 cores. Did you get any speedup? Type your answer into the chat.

 
Question 24

Test the serial code inside an interactive job. Please quit the job when done, as we have very few compute cores on the training cluster.

Note: we have seen the training cluster become unstable when using too many interactive resources. Strictly speaking, this should not happen, however there is a small chance it might. We do have a backup.

 
Question 25 Test the shared-memory code inside an interactive job. Please quit when done, as we have very few compute cores on the training cluster.
 
Question 26 Test the MPI code inside an interactive job. Please quit when done, as we have very few compute cores on the training cluster.
 
Question 27 Share a file in your ~/projects directory (make it readable) with all other users in def-sponsor00 group.
 
Question 28 Are there questions on any of the topics that we covered today? You can type your question into the chat, ask via audio (unmute), or raise your hand in Zoom.