- both issues are related to the fact that waiters for futures are notified of completion before "done" callbacks are called
- 1st issue manifested as interrupt stream event being emitted before the result of a task that logically finished first (it's in the line above in body of the entrypoint function) -> this is solved by always returning to use code a fresh future chained on the original future, because chaining is done via done callbacks (therefore the chained future will only resolve after done callbacks of the original feature are called)
- 2nd issue mainfested as sometimes (very rarely) the last stream event not being printed before stream() finishes. this is solved by ensuring we only return out of PregelRunner.tick() once all "done" callbacks are called, previously we were approximating this through use of asyncio.sleep(0) / time.sleep(0). The new solution instead waits on a threading/asyncio.Event which will only be set by the last "done" callback to fire
- order was incorrectly based on task id, instead of the correct task
path
- this requires storing task paths on checkpointers
- addition of task_path to put_writes is made backwards compatible by
checking signature on call, and treating it as an optional arg
- order was incorrectly based on task id, instead of the correct task path
- this requires storing task paths on checkpointers
- addition of task_path to put_writes is made backwards compatible by checking signature on call, and treating it as an optinal arg
Nuno Campos