.. _documentation_master:

Welcome to the SDP Resource Model's documentation!
==================================================

The SDP Resource Model is a Python application for simulating and visualising the data storage and
compute requirements of the SDP for during batch processing, given an observation schedule.

.. toctree::
    :maxdepth: 1

    quickstart
    installation
    usage/usage_index
    tutorials/tutorials_index
    api
    CHANGELOG.rst
    GitLab <https://gitlab.com/ska-telescope/sdp/ska-sdp-resource-model>

Simulation overview
-------------------

A flow chart of the simulation process is shown below (click to zoom).

.. image:: images/simulation-flow-chart.jpg
    :alt: SDP Resource Model
    :width: 600
    :align: center
    :class: margin-bottom

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Assumptions
-----------

The SDP Resource Model makes the following assumptions:

- There is only one telescope available
- Observations and data processing are executed in the order they are scheduled (unless the shuffle
  option is enabled - see :doc:`here </tutorials/run_monte_carlo_simulation>` for more information)
- Receive & real-time processing can be ignored
- Scheduling blocks can comprise multiple scheduling block instances (see :doc:`here
  </usage/inputs/configuration/observing_schedule>` for more information on how these are defined) -
  raw visibilities will accumulate in storage and batch processing will be executed after the final
  observation of the last instance. There is no data retention period for raw visibilities.
- Data products generated by pipelines are kept in data product storage from when the pipeline
  finishes until a data retention period, which is specified in the scheduling block type
  configuration and is the same for all pipelines in the block.
- Observations are delayed if there is insufficient capacity storage for raw visibilities.
- Storage for pre-processed visibilities is allocated and released for each scheduling block when
  processing of these starts and ends.
- The number of nodes allocated to an individual pipeline is fixed for the duration of the pipeline
  (set by its ``num_nodes`` parameter).
- Pipelines with the same priority level will be executed in parallel only if resources are
  available.
- There is no overhead in spinning up a node.

.. note::

    The SDP Resource Model is a work in progress and is subject to change.