Allow srun to specify the cpu binding

The task/affinity plugin needs to be selected.

m/common/slurm.nix

@@ -9,6 +9,8 @@
       "owl[1,2]  Sockets=2 CoresPerSocket=14 ThreadsPerCore=2 Feature=owl"
       "hut       Sockets=2 CoresPerSocket=14 ThreadsPerCore=2"
     ];
+
+    # See slurm.conf(5) for more details about these options.
     extraConfig = ''
       # Use PMIx for MPI by default. It works okay with MPICH and OpenMPI, but
       # not with Intel MPI. For that use the compatibility shim libpmi.so
@@ -20,6 +22,13 @@
       # When a node reboots return that node to the slurm queue as soon as it
       # becomes operative again.
       ReturnToService=2
+
+      # Track all processes by using a cgroup
+      ProctrackType=proctrack/cgroup
+
+      # Enable task/affinity to allow the jobs to run in a specified subset of
+      # the resources. Use the task/cgroup plugin to enable process containment.
+      TaskPlugin=task/affinity,task/cgroup
     '';
   };
 }