feature request: app level scheduling

[andre-merzky]

This requirement comes from Muscle3 integration (see https://github.com/radical-cybertools/other_activities/issues/89). This requires:

• exposing pilot resources via rp.Pilot instances (after PMGR_ACTIVE)
• add rp.TaskDescriptions.slots attribute (bypassing the agent scheduler)

[andre-merzky]

The following code is now possible (in branch feature/pilot_resources):

#!/usr/bin/env python3

import pprint
import radical.pilot as rp

if __name__ == '__main__':

    session = rp.Session()
    try:
        pmgr  = rp.PilotManager(session=session)
        tmgr  = rp.TaskManager(session=session)
        pdesc = rp.PilotDescription({'resource': 'local.localhost',
                                     'runtime' : 15,
                                     'cores'   : 256})
        pilot = pmgr.submit_pilots([pdesc])[0]
        pilot.wait(rp.PMGR_ACTIVE)

        nodes = pilot.nodes
        pprint.pprint(nodes)
        tmgr.add_pilots(pilot)

        td1 = rp.TaskDescription({'executable': 'hostname'})
        td2 = rp.TaskDescription({
            'executable': 'hostname',
            'ranks'     : 2,
            'slots'     : [rp.Slot.from_node(nodes[0], core_ids=[1,3]),
                           rp.Slot.from_node(nodes[1], core_ids=[2,4])]
        })

        tmgr.submit_tasks([td1, td2])
        tmgr.wait_tasks()

    finally:
      session.close(download=True)