Telcon: 2016 07 21

Participants

1. Todd Gamblin (LLNL)
2. Benedikt Hegner (CERN)
3. Brandon (NERSC)
4. Cyrus Harrison (LLNL)
5. Greg Lee (LLNL)
6. Jim Galarowicz (Krell)
7. Mario Melara (NERSC)
8. Patrick Gartung (Fermi)
9. Peter Scheibel (LLNL)

News & Discussion

1. LLNL hackathon

2. NERSC hackathon (w/ORNL, LLNL, Kitware)

• By default we'll set CRAYPE_LINK_TYPE = dynamic
  • How to set to static if needed for some builds:

class SomePackage(Package):

    def install(self, spec, prefix):
        if 'platform=cray_xc' in spec:
            env['CRAYPE_LINK_TYPE'] = 'static'

• Module support good after hackathon

  • need to make it easier to deal with externals
  • packages.yaml can get kind of large.
    • default config scope can help with this
    • need to address versions in external package files
      • detect different versions of builtin

• better cray model detection

• Currently interacting with Cray to see if we can get better clean environment.

• Brandon: thanks to everyone for coming out to the hackathon

• Cray defaults can benefit BG/Q machines

  • know where externals and such are located by default
  • Patrick: possible problems on BG/Q:
    • bgclang, gcc 4.8.4, etc. don't know where their runtimes live

3. How to deal with changing hashes and reinstalls: #1325
4. Need better ways to maintain a production spack package repository
5. a number of bugs blocking this (#1178)
6. Working on fixes
7. possible solutions hash issues: 1. concretizing based on what is already installed
   • This is planned! but needs better constraint solving
   • We've got a prototype implementation of better constraint solving from the NERSC hackathon
     • thanks to Ben Boeckel from Kitware
   • NOTE for @citibeth: this would definitely be optional and we'd allow clean-slate installs too. 1. Bring back "Views" (from the paper)
   • project spack space onto smaller space (symlink tree) that users can rely on
   • module names don't have hashes; same view can be regenerated even if hash changes
   • new view might have new versions of things
   • allow for seamless upgrades 1. more extensive package testing
   • LLNL can do AWS testing
   • Benedikt: CERN could do CentOS 7 and gcc testing
     • CERN needs testing anyway
     • nightly coverage of a larger portion of the Spack space.
     • Todd to follow up w/Benedikt
   • NERSC could also look into testing on Cray platforms.
     • might have issues using enormous amounts of CPU time
     • smaller set of packages could be workable.
     • Brandon to investigate at NERSC.

• Thoughts?

4. OpenSSL pinging will be removed #1333

5. Peter:

• addressing some issues with properly mirroring packages that have expand=False set in version directive
• also going to fix issues with caching tarballs downloaded from Spack create.

6. Cyrus: wants more consistent optional Fortran support.

• Need a set of global variants.
• need better fortran compiler support in Spack (model as dependency)
• need variant forwarding to sub-dags (Greg Becker to work on this)
  • Patrick Gartung:
    • Adam Lyon did some similar work to add C++14 to dependencies
    • added ways to propagate C++14 variants in DAG
    • Todd: look at Adam Lyon's Spack fork

7. Many other PRs merged (see Pulse!)