ef3f8d221a5afefb01d655448ce7e3f537399810,src/python/pants/engine/exp/engine.py,LocalMultiprocessEngine,reduce,#LocalMultiprocessEngine#Any#Any#,446

Before Change

    // ExecutionGraph nodes move from `pending_submission` to `in_flight` to `satisfied_promises`.
    pending_submission = {}
    in_flight = {}
    satisfied_promises = set()

    def submit_satisfied_pending():
      for promise, plan in pending_submission.items():
        if plan.promises.issubset(satisfied_promises):

After Change

    for step_batch in self._scheduler.schedule(build_request):
      if not step_batch:
        // A batch should only be empty if all dependency work is currently blocked/running.
        if not in_flight and not pending_submission:
          raise Exception("Scheduler provided an empty batch while no work is in progress!")
      else:
        // Submit and wait for work for as long as we"re able to keep the pool saturated.
        pending_submission.update(step_batch)
        while submit_until(self._pool_size) > 0:

Instances