Conference call notes 20161026

(back to Conference calls)

Notes on the 62nd EasyBuild conference call, Wednesday October 26th 2016 (5pm - 6pm CET)

Attendees

Alphabetical list of attendees (4):

• Joachim Hein (Lunarc, Lund University, Sweden)
• Kenneth Hoste (HPC-UGent)
• Bart Oldeman (McGill University, Canada)
• Guilherme Peretti Pezzi (CSCS, Switzerland)

Agenda

• update on EasyBuild 3.0 roadmap: https://github.com/hpcugent/easybuild/issues/255
  • little progress during last couple of weeks...
• update on RPATH: still WIP, see https://github.com/hpcugent/easybuild-framework/pull/1942
  • compiling GCC 5.4.0 with --rpath enabled fails with a weird problem...
• update on deprecating of old/inactive toolchains
• instruction set and cross compiling (e.g. --enable-avx2 for FFTW)
• Q&A

Notes

EasyBuild 3.0 roadmap

• https://github.com/hpcugent/easybuild/issues/255

RPATH support

• https://github.com/hpcugent/easybuild-framework/pull/1942
• building GCC 5.4.0 with --rpath enabled fails in a weird way
  • /usr/bin/install: cannot stat '.libs/libcc1.so.0.0.0': No such file or directory
  • libtool command that is supposed to generate that file is skipped somehow
  • no other errors found in the build log, nor in the rpath wrapper logs...
  • https://gist.github.com/boegel/263ca62858b4785de533a6b50929e0e0
• considered success if OpenFOAM can be built on top of foss/2016b with --rpath enabled
• Bart: alternate approach to using RPATH: use EasyBuild in Nix (which does RPATH by default)
  • this works to build HPL/OpenFOAM with iompi toolchain

deprecating old/inactive toolchains

• https://github.com/hpcugent/easybuild/wiki/Deprecated-toolchains
• about 100 software pkgs would be lost because they're only available with old toolchains
• AP KH: open issue with a list
• --try-toolchain=foss,2016a to the rescue?

Cross compiling

• e.g. issue with FFTW mentioned by Joachim on ML: configure with --enable-avx2, or not?
  • add FFTW easyblock that figures out which processor features are available, determine which configure options should be used?
  • not using AVX2 for FFTW may cause 4x slowdown on Haswell, in theory...
• FFTW is just one example, there are others
• for FFTW specifically it may be OK, since it builds 'fat' binaries with runtime detection
  • similar approach in recent OpenBLAS
• other example of cross compilation: https://portal.tacc.utexas.edu/user-guides/stampede#knl-building
• open issue in framework repo to track what is needed for this?
• mostly a documentation problem to mention how cross compilation is supported now...
  • e.g. build on every cluster + --optarch control

Other

• decouple EasyBuild framework releases from updates to easyconfigs(/easyblocks)?

  • OK, but only if someone else helps with this...
  • stable branch in easyblocks/easyconfigs repositories next to develop (considered unstable)?
  • should be mentioned on the mailing list
    • what needs to change in the contribution workflow for this?
    • who has time to look into more frequent easyblocks/easyconfigs releases?
    • test reports should be done on top of EasyBuild framework master + easyblocks/easyconfigs stable
    • develop branch should be kept up-to-date with stable, ideally automagically...

• Joachim: HDF5 1.10 support?

  • no PRs yet for it, maybe because other projects are not compatible with it yet?
  • Joachim is planning to look into sending a PR for this

• possible EasyBuild User Meeting coming up in Feb'17...

  • keynote?
  • tutorial on easyblocks would be nice
    • some (slightly outdated) docs available:
      • https://github.com/hpcugent/easybuild/wiki/Tutorial%3A-building-WRF-after-adding-support-for-it
      • http://users.ugent.be/~kehoste/EasyBuild-basics-CSCS_20150908.pdf