Using SALLOC Command 

With the "salloc" command you can obtain an interactive SLURM job allocation (a set of nodes), execute a command, and then release the allocation when the command is finished.

If you would like to allocate resources on the cluster and then have the flexibility of using those resources in an interactive manner, you can use the command "salloc" to allow interactive use of resources allocated to your job. In the next example we will request 5 tasks and 2 hours for allocation:

$ salloc -n 5 --time=2:00:00

salloc: Pending job allocation 45924
salloc: job 45924 queued and waiting for resources
salloc: job 45924 has been allocated resources
salloc: Granted job allocation 45924

$ srun hostname
bee025
bee025
bee025
bee025
bee025

$hostname
hive01.haifa.ac.il

$exit
exit
salloc: Relinquishing job allocation 45924
salloc: Job allocation 45924 has been revoked.

After that request enters the job queue just like any other job, and "salloc" will tell you that it is waiting for the requested resources if there aren't enough at the moment. When "salloc" tells you that your job has been allocated resources, you can interactively run programs on those resources with "srun" command. The commands you run with "srun" will then be executed on the resources your job has been allocated. If you finished your work before the allocated time or if you didn't allocated time at all, use "exit" command to stop the allocation permenantly

Warning: All commands that you are executing after your job has been allocated resources must run with "srun" command, otherwise those command will be executed from the access node and not on the allocated resources you asked for, you can see it in the example above.