How to update job node number in Slurm?

Question

I have a pending job and I want to resize it. I tried:

scontrol update job <jobid> NumNodes=128

It does not work.

Note: I can change the walltime using scontrol. But when I try to change number of nodes, it failed. It looks like I can change the nodes according to this page http://www.nersc.gov/users/computational-systems/cori/running-jobs/monitoring-jobs/.

Answer 1

Here is a solution I got from NERSC help desk (Credits to Woo-Sun Yang at LBNL):

$ scontrol update jobid=jobid numnodes=new_numnodes-new_numnodes

E.g. $ scontrol update jobid=12345 numnodes=10-10

The trick is to have numnodes in the above format. It works for both shrinking and expanding your nodes.