Present: Roland, Deborah, Steve, Lucas, Peter, Beyhan, Maxwell, Jordan, Noora, Yosef, Zach

Chair: Peter

Minute taker: Deborah

Minutes:

• New ETK release done!

• Kuibit release wrong on download page
  • will be fixed
• Bitbucket issues
  • Zach been working on figuring out what exactly needs to be done to convert over to github with the help of clankers
    • has simplified the process greatly into just a few steps
    • some trickiness about mapping bitbucket users to github users
      • maybe just list the bitbucket user
      • maybe just email address if that’s possible
      • clankers didn’t have a plan for handling users yet
        • was just going to do names in plain text
        • Zach has changed this to make a user map between bitbucket and github users
• Accumulated updates after the release
  • CarpetX / AMReX
    • there will be a breaking change to CarpetX which we wanted to do early in the release cycle
  • McLachlan
    • updates being brought back into focus
• Mailing list questions
  • Jordan about using GetComponents
    • can it be used to update everything to the newest release?
    • Roland: the script doesn’t change branches so GetComponents can’t switch you to a new release
      • typically just create a new Cactus directory with the new release
    • Steve: it’s a feature we could add, in principle, if there is interest
  • Jordan about bug in CarpetRegrid2
    • has opened a ticket
  • Question about IllinoisGRMHD C2P failure and Psi4 extraction
    • Psi4 aspect has been answered
    • still waiting for help about IllinoisGRMHD part
      • it’s crashing immediately
      • getting nans
      • Zach: in IllinoisGRMHD itself, where that error message appears, give some helpful tips about how to go about debugging
        • turn on poisoning
          • likely an issue of feeding in some data but not all the data that illinois GRMHD needs
        • will reply to the email
• Open tickets
  • Test Derivs fails on stampede with NaNs
    • Steve reproduced the bug but with the help of clankers may have found a solution
    • Needs more eyes
  • Split the ET
    • right now we have a giant thornlist with basically two sets of thorns (Carpet and CarpetX)
    • could split up the Carpet and the CarpetX thornlists
    • could help with code duplication
    • comes with some tradeoffs
    • Noora
      • encountering an issue with compiling
        • when compiling, it was pulling the Carpet versions instead of the CarpetX versions
        • some of the thorns aren’t part of the current ETK release
    • Maxwell
      • what about splitting them but keeping the name differences?
    • Steve
      • if we get rid of the X in some names, then things like TwoPunctures don’t have to be duplicated
    • Lucas
      • which thorns can be made compatible across drivers?
        • twopunctures seems like an exception
      • at some point, we’re probably going to have a breaking change
    • Roland
      • we can make some level of compatibility with just a little bit of performance loss
    • Steve
      • went through with the help of AI to see what thorns would be easy to make compatible with both
    • Yosef
      • development and code maintenance is mostly a volunteer effort
      • deprecate Carpet once CarpetX can replicate all science
      • proposes that long term compatibility doesn’t need to be an overarching goal
    • Steve
      • agrees that we will have to move on and abandon code eventually
      • needs further discussion
    • Zach
      • solving many of these issues could be done by formalizing Roland’s tool that creates a thornlist from the parameter files
      • more informative error messages would be useful as well
    • Jordan
      • can someone explain the difference between Carpet and CarpetX?
        • Lucas and Zach: it’s very nontrivial. loops are different for example. ccl files differ a bit
        • Zach: much easier with clankers
    • Yosef
      • which thorns are actually compatible with both
        • Steve: shared a markdown file with that
        • Roland: only a few things, like Time
      • his impression is that there’s just a handful of thorns that are the same and most things are different
      • treats them as entirely different codes
    • Peter
      • what’s the timescale for actually getting CarpetX to the point of replacing Carpet for production runs
      • let’s discuss this further in future meetings
• AOB
  • Steve
    • made a few updates to the ETK tutorial server
    • should run more smoothly now