Wayne State University

AIM HIGHER

Wayne State University

High Performance Computing Services

8. Utilizing the Mass Queue

To review the previous section, press BACK. To return to the index, press INDEX.

Log in to the Grid.

There are two primary queues accessible to all Grid users. The wsuq and the mwsuq.

wsuq:
  • provides up to 960 compute cores
  • allows for up to 240 jobs in queue
  • jobs run on public nodes only
mwsuq:
  • has no compute core limit
  • allows for up to 2400 jobs in queue
  • jobs run on all nodes including nodes owned by groups with preemption capabilities

Which queue should you use?

wsuq:
  • if you only need to run a limited number of jobs
  • and you don't want to have those jobs suspended
  • or if they will use a significant amount of walltime
mwsuq:
  • if you want to run hundreds of jobs all at once
  • or if you want to target resources on nodes that aren't in the wsuq
  • and you don't mind if some of them are suspended

Note: If the entire wsuq is full then the PBS job scheduler will use a fair share algorithm to determine whether older jobs should be suspended to allow newer jobs to run. If you have many jobs that have been running for a long time then it is possible that you may have jobs suspended in the wsuq.

Note: It is not easy to predict when groups will use their express queues to preempt jobs.

To specify that you would like to run on the mwsuq you will want to modify the #PBS -q line to read:

#PBS -q mwsuq

Or to specify that you would like an interactive shell on an mwsuq accessible node you will use the following command:

qsub -I -q mwsuq

You can also submit jobs to wsuq with the following command

qsub -I -q wsuq

This is how the screen would look like and you can see the change in hostname as shown in the coloured boxes

qme

The next section deals with utilizing resources on the Grid. NEXT.

Computer Center Services * 5925 Woodward Avenue Detroit, Michigan 48202