task runners as actors #167
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remove old implementation and start scheduling task runners as if they were normal actors, preventing WS of task runners. this implementation uses a counter of remaining tasks. whenever a task is added to the global task runner messageq, increase the count and wake up and task runner. task runners are awaken as needed, otherwise they are unscheduled.
clean up of tasks. add function for getting the runtime type of tasks
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| // if there are message to process, schedule task runner | ||
| uint32_t counter = __pony_atomic_load_n(&remaining_tasks, PONY_ATOMIC_RELAXED, uint32_t); | ||
| if(counter>0 && is_unscheduled((pony_actor_t*) this_encore_task)){ |
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One reason of treating task-runner as an actor is to get rid of polling, but isn't if block here polling?
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is the line 341 polling?
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No, I don't think so. However, on line 332, it's checking if task-runner needs to be scheduled. If actors are changes to using polling, it would be push(sched, actor) if actor_has_msg. Conversely, in the current implementation which does not use polling, actors are scheduled after they receive messages. If one actor hasn't received any message, there's no overhead at all in the schedule loop.
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I see your point, and I'll figure out a way of keeping the task runners as close as possible to actors. However, there's a difference with actors and, currently, I do not use the messageq of the task runners since they pick up things from a mpmcq. In the not so distant future, I'd like to implement a strategy similar to lazy scheduling for tasks (http://dblp.uni-trier.de/rec/bibtex/journals/toplas/TzannesCVB14), since I believe it makes sense. There'll be discussion about this, but I believe the idea solves a couple of problems altogether.
remove old implementation that alternate between a task runner and an actor. Schedule task runners as if they were normal actors, preventing WS of task runners.