Last Week in Pony - December 18, 2022
The big news for this week is that we merged and release a safety fix that can have a large impact on performance for applications that send lots of messages that need to be traced by the garbage collector. We’ll be incrementally adding back in performance as we make the compiler smarter.
Items of Note
The Performance Hit is Here
The fix was merged on the afternoon of the 13th. Nightlies starting from the 14th and the 0.52.3 release from Friday have the safety fix in place.
MacOS on Intel is no longer a fully supported platform
A few weeks back, we announced that we would be dropping support for MacOS on Intel. At the time, we said that we would be doing it “before the end of the year”, well, “before the end of the year is here”. On December 12th, we merged the changes to drop MacOS on Intel support from ponyc, corral, and ponyup.
We have an open Zoom meeting every Friday for the community to get together and well, do whatever they want. In theory, Sean T. Allen “owns” the meeting and will often set an agenda. Anyone is welcome to show up and participate. Got a Pony related problem you need help solving and prefer to do it synchronously? Give Office Hours a try.
The December 16th “Office Hours” were attended by Adrian Boyko, Sean T. Allen, Joe Eli McIlvain, and Red – the topic was Sean’s interesting proposal to replace Pony’s existing centralized “Cycle Detector” with a decentralized alternative.
Whether centralized or distributed, a cycle detector’s job is to look for sets of actors that are collectively involved in a reference cycle. For example, if “➞” means “references” and we have a situation where A➞B, B➞C, and C➞A, then actors A, B, and C form such a cycle.
Actors are typically “reaped” when their reference count goes to zero and they don’t have any other incoming messages to process. However, when actors form a reference cycle they will still have non-zero reference counts after all the other actors have forgotten about them, and this will prevent them from being reaped even if none of them have further messages to process. Recognizing the cycles in such scenarios lets Pony reap actors that would otherwise persist past any usefulness.
The dynamics of a distributed cycle detection protocol are reasonably complicated, especially when you consider the infinite number of ways that N actors can reference each other. To help make sure we don’t miss any subtle details, Joe has volunteered to model the protocol using Alloy. He showed us some of the initial work he has done on the model and introduced us to the new temporal logic which was introduced in Alloy version 6.
We then spent some time talking through specific scenarios to learn how Sean’s protocol would deal with each: actors arranged in simple loops, in completely connected graphs, and in overlapping combinations of simpler scenarios (like two loops that share one actor in common).
All-in-all, it was a very productive discussion and it seems as though the distributed cycle detection protocol is off to a good start.
Interested in giving attending Office Hours sometime? There’s a calendar you can subscribe to to stay up-to-date with the schedule. We do our best to keep the calendar up-to-date.
Pony is a volunteer driven project. Nothing gets down without someone volunteering their time and helping to push things forward. Yes, there are folks who dedicate more time than others and a core team that dedicates time specifically for guiding Pony’s development. Everyone’s time is limited, so each week, we highlight a couple of issues that we hope will inspire someone to volunteer their time to help fix.
In addition to our highlighted issues, you can find more that we are looking for assistance on by visiting just about any repository in the ponylang org and looking for issues labeled with “help wanted”
If you are interested in working on either issue or any other issue from a Ponylang repository, you can get in touch on the issue in question or, even better, join us on the Ponylang Zulip to strike up a conversation.
This week’s issues as selected by Ryan A. Hagenson are:
Windows releases contain unneeded files
The Windows PowerShell script that builds
ponyc includes files that are not needed. As we have very few Pony on Windows experts around, someone familiar with PowerShell could be a real help to us! Someone taking this issue should feel comfortable working with PowerShell – other than that, follow what the issue says.
Update Windows LibreSSL version
Calling all Pony on Windows users! If you want a relatively easy way to contribute to Pony, we need someone to update the version of LibreSSL that
crypto is built against. We currently are building against 3.5.3 (released May 18th, 2022) with the latest release being 3.7.0 (December 12th, 2022). Someone taking this issue should feel comfortable working with PowerShell and build systems.
Major changes in Pony go through a community driven process where members of the community can write up “requests for change” that detail what they think should be changed and why. RFCs can range from simple to complex. We welcome your participation.
This week, we’ve had single requests for an RFC. Requests for RFC means that either the Pony core team or a community member is requesting that someone write an RFC to address a specific issue.
Requests for someone to create an RFC for “issue X” from a Pony user.
Last Week In Pony is a weekly blog post to catch you up on the latest news for the Pony programming language. To learn more about Pony, check out our website, our Twitter account @ponylang, or our Zulip community.
Got something you think should be featured? There’s a GitHub issue for that! Add a comment to the open “Last Week in Pony” issue.
Interested in making a change, or keeping up with changes to Pony? Check out the RFC repo. Contributors welcome!