Chapel project meeting: 2025-12-16 (agenda items, meeting link, notes)

[github-actions[bot]]

This discussion is for the weekly Chapel project meeting.

Date/Time: 2025-12-16 at 10am PT
Join the meeting using this Teams link

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Prior to the meeting, propose any agenda items using comments below. After the meeting, rough notes will be added in comments.

Typically, these meetings consist of:

• News: Quick updates or announcements to keep people in the loop on key efforts or topics
• Demos: Have something cool to show off? Do it in a ~5-minute demo
• Short Topics: Have something that needs a quick discussion, description, or straw poll? Propose a ~5-minute discussion topic
• Longer Topics: If you have a topic needing more time, propose it with an estimated duration and we'll try to fit it in.

If you'd like to propose an item in any of these categories, please reply to this discussion.

In addition to the above sections, we have some standing agenda items, such as:

• Triage: What is the state of testing and are there issues that need more attention?
• User Issues: What new user issues have come up in the past week, and which should we prioritize?
• Q&A: Have something you want to ask, but not on the clock? We'll open the floor to Q&A as the official meeting wraps up.

[lydia-duncan]

Here's today's user issues report!

[bradcray]

Agenda / Notes

News/Announcements

• Last week's TSC meeting focused on the chair, new members, and Chapel's logo:

  • slides: https://github.com/chapel-lang/TSC/blob/main/meetings/2025-12-11-Chapel-TSC.pdf
  • notes: https://github.com/chapel-lang/TSC/blob/main/meetings/2025-12-11-notes.md

• Published 2nd part of "Transformers From Scratch in Chapel and C++" Friday

  • author: Thitrin Sastarasadhit
  • link: https://chapel-lang.org/blog/posts/transformer-part2/

• Video from Brad + Jade's Arkouda talk/demo now on UW eScience YouTube:

  • link: youtube.com/watch?si=c_o0S6_FV-XKS72i&v=kOKmJdimYnI&feature=youtu.be

• Chapel version 2.7 is scheduled to be released on Thursday

  • slight hitch due to mason bug slipping in
  • fix merged last night; scrambling to re-roll necessary artifacts today
  • thanks to all contributors and those working on the release itself!

• Michelle alerted us to 1 Trillion Row Challenge

  • Dask completes in ~8.5 minutes
  • seems like Arkouda (or even native Chapel?) could do better...
  • https://github.com/coiled/1trc
  • Jade: looked at 1TRC code -- basically min/max/groupby/sort
    • so, stuff that Arkouda is good at
    • less than 10 lines; could probably just do it, where getting the data
      is probably the biggest/main challenge
  • Michelle: Reminder that Andy did the 1BRC
    • blog article here: https://chapel-lang.org/blog/posts/1brc/
    • think input was CSV for that vs. Parquet?
  • Engin: 1 caveat: given amount of storage, would have to read direct from S3
    • maybe arrow can do this directly
    • might also be able to generate our own copy of the data? (which might
      also help with performance)
  • Michelle: Matt has been doing similar Arkouda computations with similar
    data set sizes

• Holidays coming up... I propose we skip this meeting Dec 23 and 30

Triage Status

• Engin: mid-rotation update
  • didn't see anything surprising
  • Arkouda fix is resolving today

User Issues

• Lydia: weekly report
  • 2 new user issues:
    • documentation request from Damian for using transmute() routine
      • Lydia discovered we didn't document that when adding it
      • probably a few other issues to be opened there...
    • VSCode extension request from jmag722 for being able to automate docstrings
  • no newly resolved issues
    • but one resolved the week prior was tagged "user" after the fact
      • fix to obfuscated internal error
  • Jade: for error message, it's done, but not yet tested
  • Brad: Tom Westerhout wondering about passing multidim Chapel arrays to Python
    • Jade: Should be supported with the Python module

Demos

Jade: parallel testing in mason
- 3+ min test run goes down to 56 seconds on laptop

DavidL: progress on making runtime into a dynamic library
- now works with comm=none
- rewired Makefiles / flags to support it
- used linker warning about non-static flags to find needed symbols
- uses a macro to expand uses of runtime calls to use these
- working on debugging comm=gasnet now...

Discussion Topics

Post-meeting

Office Hours / Q&A

• some more discussion about making a local copy of the 1TRC data set

  • seems plausible and may help perf
  • a more "typical" end-user story would be to read directly from S3
  • ideally we'd do both, but to sprint to a sol'n, local disk probably faster
    • both in terms of time-to-solution and execution time?

• Daniel did branch+tag of updated 2.7

  • Jade will fire off tarball build

TODOs / Open Issues