Introduction to High-Performance Computing: Instructor Notes

Cluster roleplay instructions (from 04-scheduler)

To do this exercise, you will need about 50-100 pieces of paper or sticky notes.

1. Divide the room into groups, with specific roles.
   • Pick three-four people to be the “scheduler”
   • Have the remaining one-third of the room be “users”, given several slips of paper (or post-it notes) and pens
   • Have the remaining two thirds of the room be “compute nodes” Make sure everyone knows what their roles are. Have the “users” go to the front of the room (or the back, wherever there’s space for them to stand) and the “schedulers” stand between the users and “compute nodes” (who should remain at their seats).

2. Divide the pieces of paper / sticky notes among the “users” and have them fill out all the pages with simple math problems and their name. Tell everyone that these are the jobs that need to be done and correspond to their computing research problems.

3. Point out that we now have jobs and we have “compute nodes” (the people still sitting down) that can solve these problems. How are the jobs going to get to the nodes?
   The answer is the scheduling program that will take the jobs from the users and deliver them to open compute nodes.

4. Have all the “compute nodes” raise their hands. Have the users “submit” their jobs by handing them to the schedulers. Schedulers should then deliver them to “open” (hands-raised) compute nodes and collect finished problems and return them to the appropriate user.

5. Wait until most of the problems are done and then re-seat everyone.

6. Follow-up discussion: what would happen if a node couldn’t solve the math problem? It might be important to indicate the resources that your job needs to run. Add other parallels that will be coming up in the next section of the lesson.