Add "Runtime basics" to the tutorial

[SeanTAllen]

While discussing ponylang/ponylang-website#502 (add quiescence FAQ).

• Garbage collector basics (there are 2 entries in the appendix)
• Quiescence
• ASIO system
• Env.exitcode

Perhaps a link to runtime options, also information on how to find more information.

[rhagenson]

Any thoughts on where this chapter should go? My opinion in after Packages and before Testing as the former ends on the Standard Library and the latter starts into sort of advanced Pony usage.

[rhagenson]

Adding a task list to ensure I stay organized (this task list was build over the course of writing):

• Add new chapter and weight accordingly in config for menu placement
• Add section on on Env.exitcode
• Add section on garbage collector
• Add section on ASIO system
• Add section on quiescence (see Section about quiescence as it relates to program termination. #157, as well)
• Add Backpressure/Muting section
• Add section on Runtime Options

[rhagenson]

After re-reading both the runtime-related appendices (Memory Allocation at Runtime, and Garbage Collection with Pony-ORCA), I think this information should be moved into the new chapter rather than repeated in the appendix.

Also, Memory Allocation at Runtime ends with an ellipsis. Was there something more intended to go there?

[SeanTAllen]

@rhagenson I have no idea why the ellipsis is there.

[SeanTAllen]

@rhagenson do you have all the info you need?

[rhagenson]

@SeanTAllen I believe so. I have begun work over on https://github.com/rhagenson/pony-tutorial/tree/runtime-chapter Mostly so far it has been a refactor to move the runtime content from Appendices into the new chapter and rewrite that content to stress the pertinent details.

[rhagenson]

Friendly update that I am back on top of this. Had to take a hiatus while, among other things, I prepared a tutorial submission for the largest conference in my field. That tutorial will include Pony, if accepted.

Sort of preemptive question so feel free to answer solely off the cuff: what have been some past references for any of this information? E.g., blog post on how the ASIO system works, video on quiescence, past issue/PR that involved ample discussion of garbage collection, etc. Looking to make the language consistent between what has been deemed good/helpful in the past and the tutorial.

[SeanTAllen]

re: gc... see the orca paper: https://www.ponylang.io/media/papers/orca_gc_and_type_system_co-design_for_actor_languages.pdf and this video from @aturley: https://vimeo.com/181099993

[rhagenson]

Already had the ORCA paper, but not the video. Thank you for both.

Any similarly useful references for the other topics?

[EpicEric]

There are some early discussions from the beginning of the #runtime stream in Zulip (that were actually copied from the Slack) that cover a few runtime topics.

[rhagenson]

@EpicEric I had no idea there even was a runtime stream on Zulip. Thank you for pointing me toward it.

[rhagenson]

Reminder to self (and noted here for others to hold me to it):

• Find good place to mention the number of scheduler threads is N where N is core count + 1 ASIO thread

The way I have it written now this detail would be forced or detract from the point wherever I put it. I am sure the content will change so not going to force it now when later unforced addition is still possible.

[SeanTAllen]

Number of scheduler threads is N where N is the core count. There is additionally an asio thread that handles receiving asio messages, however, it never runs any actors. When we say "scheduler threads", the asio thread is not included in that.