How to Run AutoPot on a Cluster?
================================

To run AutoPot on a cluster, additional configuration is necessary. First, the
compute nodes need to access the database through a TCP connection.

This can be done by adding the host of the ZEO server in ``motoko.yaml`` for
each task:

.. code-block:: yaml

   select:
     host: zeo://cluster_name:8010

The number at the end is the port, which needs to be different for every task.

Further, specify a submission manager, such as Slurm, and add options. This can
be done at the workflow level by appending the following to ``motoko.yaml``:

.. code-block:: yaml

   generator: slurmCoat

   slurm_options:
     - nodes=1
     - ntasks=1
     - cpus-per-task=1

A complete ``motoko.yaml`` file for cluster usage will look like this:

.. code-block:: yaml

   task_managers:
     select:
       host: zeo://cluster_name:8010

     md_select:
       host: zeo://cluster_name:8011

     eam:
       host: zeo://cluster_name:8012

     vasp:
       host: zeo://cluster_name:8013

     train:
       host: zeo://cluster_name:8014

   aliases:
     sp_calc: vasp

   orchestrator: orchestrator.main

   generator: slurmCoat

   slurm_options:
     - nodes=1
     - ntasks=1
     - cpus-per-task=1

In many situations, different Slurm setups are needed for different tasks. For
example, MD simulations may run on one core, but VASP calculations may run on a
whole node. This can be realized by adding ``slurm_options`` to the run
parameters in the ``bd.yaml`` file corresponding to the ``vasp`` task:

.. code-block:: yaml

   study: sp_calc

   job:
     cfg_fname: str
     incar_fname: str

   run:
     slurm_options: list

   job_space:
     incar_fname: INCAR_ase

   run_params:
     slurm_options:
       - nodes=1
       - ntasks=64
       - cpus-per-task=1

Any Slurm option defined in the ``bd.yaml`` file of a task will overwrite the
options defined on the workflow level.