Priority
========

PSMN use the "priority/multifactor" algorithm for **pending** jobs, which is:

    - Precision (more precises submissions gain more priority [cpu, mem, time])
    - Weigth (larger jobs gain more priority)
    - Fair Share (resources [#tres]_ **usage** is equally distributed among **users**: the more you have already running, the less priority you get for your pending jobs)
    - Aging, QoS (these two influence priority calculation)
    - Best Effort (if there is room for small and **short** jobs, they may go through, **respecting** Fair Share priority)

The Fair Share algorithm use a 3 weeks sliding window.

**It is an automated process on which the PSMN Staff has no control.**

.. TIP::

    As a quick rule of thumb, it's important to keep in mind that the more resources your job requests (CPUs, memory, nodes, and time), the longer it *may* have to wait in queue before it could start.

    In other words: accurately requesting resources to match your job's needs will minimize your wait times.

You can display the "expected start time" [#squeue]_ of your jobs:

.. code-block:: bash

    $ squeue --me --start

    $ squeue --me --states=PENDING --sort=S,Q --format="%.10i %.12P %.8j %.8u %.2t %.10M %.6D %.4C %R %Q %.19S"

You can also display the priority calculation [#sprio]_ for your jobs:

.. code-block:: bash

    $ sprio -u $USER


.. [#tres] TRES, Trackable RESources: CPU, GPU, memory, time

.. [#squeue] You can get the complete list of parameters by referring to the ``squeue`` manual page (``man squeue``).

.. [#sprio] You can get the complete list of parameters by referring to the ``sprio`` manual page (``man sprio``).