How to activate hyperthreading for ipcluster and MPI - jupyter-notebook

Question

I am starting an IPython cluster with an MPI engine to execute a jupyter notebook on multiple processes:
ipcluster start --engines=MPI -n 6 --profile=mpi
The machine has 6 cores so this works without an issue. However, I would also like to use its 12 threads. How do I tell IPython/the ipcluster command to activate hyperthreading (i.e. pass --use-hwthread-cpus to the mpirun/mpiexec command it executes)?
Error message I receive when trying the above ipcluster command with 12 nodes:
2023-01-06 14:01:35.586 [IPClusterStart] Starting 12 engines with <class 'ipyparallel.cluster.launcher.MPIEngineSetLauncher'>
2023-01-06 14:01:35.688 [IPClusterStart] WARNING | engine set stopped 1673010095: {'exit_code': 1, 'pid': 187667, 'identifier': 'ipengine-1673010095-187622'}
2023-01-06 14:01:35.689 [IPClusterStart] ERROR |
Engines shutdown early, they probably failed to connect.
Check the engine log files for output.
If your controller and engines are not on the same machine, you probably
have to instruct the controller to listen on an interface other than localhost.
You can set this by adding "--ip=*" to your ControllerLauncher.controller_args.
Be sure to read our security docs before instructing your controller to listen on
a public interface.
2023-01-06 14:01:35.690 [IPClusterStart] ERROR | Engine output:
Invalid MIT-MAGIC-COOKIE-1 key--------------------------------------------------------------------------
There are not enough slots available in the system to satisfy the 12
slots that were requested by the application:
/****/venv/bin/python
Either request fewer slots for your application, or make more slots
available for use.
A "slot" is the Open MPI term for an allocatable unit where we can
launch a process. The number of slots available are defined by the
environment in which Open MPI processes are run:
1. Hostfile, via "slots=N" clauses (N defaults to number of
processor cores if not provided)
2. The --host command line parameter, via a ":N" suffix on the
hostname (N defaults to 1 if not provided)
3. Resource manager (e.g., SLURM, PBS/Torque, LSF, etc.)
4. If none of a hostfile, the --host command line parameter, or an
RM is present, Open MPI defaults to the number of processor cores
In all the above cases, if you want Open MPI to default to the number
of hardware threads instead of the number of processor cores, use the
--use-hwthread-cpus option.
Alternatively, you can use the --oversubscribe option to ignore the
number of available slots when deciding the number of processes to
launch.
--------------------------------------------------------------------------
2023-01-06 14:01:35.690 [IPClusterStart] ERROR | IPython cluster: stopping
2023-01-06 14:01:35.691 [IPClusterStart] Stopping controller
2023-01-06 14:01:35.691 [IPController] CRITICAL | Received signal 15, shutting down
2023-01-06 14:01:35.692 [IPController] CRITICAL | terminating children...
2023-01-06 14:01:35.816 [IPClusterStart] Controller stopped: {'exit_code': 0, 'pid': 187624, 'identifier': 'ipcontroller-187622'}
2023-01-06 14:01:35.816 [IPClusterStart] Stopping engine(s): 1673010095