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				Software Heritage Scheduler Simulator
				=====================================

				This component simulates the interaction between the scheduling and loading
				infrastructure of Software Heritage. This allows quick(er) development of new
				task scheduling policies without having to wait for the actual infrastructure
				to perform (heavy) loading tasks.

				Simulator components
				--------------------

				- real instance of the scheduler database
				- simulated task queues
				- simulated workers
				- simulated load tasks
				- simulated archive -> scheduler feedback loop

				douarddaUnsubmitted Done Inline Actions this list of items is not very clear. May be rephrased a bit for better clarity. Especially the last one on the feedback loop douardda: this list of items is not very clear. May be rephrased a bit for better clarity. Especially…
				Installing the simulator
				------------------------

				The simulator depends on SimPy and other specific libraries. To install them,
				please use:

				.. code-block:: bash

				pip install 'swh.scheduler[simulator]'

				Running the simulator
				---------------------

				The simulator uses a real instance of the scheduler database, which is (at
				least for now) persistent across runs of the simulator. You need to set that up
				beforehand:

				.. code-block:: bash

				# if you want to use a temporary instance of postgresql
				eval `pifpaf run postgresql`

				# Set this variable for the simulator to know which db to connect to. pifpaf
				# sets other variables like PGPORT, PGHOST, ...
				export PGDATABASE=swh-scheduler

				# Create/initialize the scheduler database
				swh db create scheduler -d $PGDATABASE
				swh db init scheduler -d $PGDATABASE

				# This generates some data in the scheduler database. You can also feed the
				# database with more realistic data, e.g. from a lister or from a dump of the
				# production database.
				python3 -m swh.scheduler.simulator fill_test_data

				# Run the simulator itself, interacting with the scheduler database you've
				# just seeded.
				python3 -m swh.scheduler.simulator run