Slurm FAQ

What partition should I use?

There are two partitions, phi and phi_test, are available at this moment. All 16p and 18p nodes are configured in phi partition, only small fraction of 18p nodes are in phi_test partition. Please only use phi_test for jobs that testing 18p. Right now the default partition is phi, using '-p phi_test' if you don't want to use phi partition. For the most updated partition configuration, please check LQCD web portal Slurm Parttition page.

What is the default MPI?

Right now there is no default MPI configured in Slurm. User has to manage mpirun in his/her job script. The code (and included libraries) can be exactly the same as that used on the PBS.

What is the largest job can be run on 18p nodes?

The largest single 18p switch fabric is 44 nodes,  so nothing larger than that can run when using --constraint=18p. But after July 1, user can request up to 256 16p nodes in a single job. 

How can I request nodes booted in flat-quad mode?

Using '--constraint=flat,quad ' or '-Cflat,quad' option to request the node in flat-quad mode, if there are not enough this kind of node, Slurm will reboot the node to the requested mode. In the same way, if a user needs cache-quad node, he/she must use '--constraint=cache,quad ' or '-Ccache,quad' option.

How can I request only 18p/16p nodes?

Using '--constraint=cache,quad,18p ' or '-Ccache,quad,18p' option to request 18p nodes in cache-quad mode, or  '--constraint=flat,quad,18p ' or '-Cflat,quad,18p' option to request 18p nodes in flat-quad mode. Same as for 16p nodes.