LEP TF meeting



Dirk Duellmann (CERN) , Ulrich Schwickerath (CERN)

~ fortnightly LEP working group meeting - currently joint with CERNLIB community port  working group.

LEP TF meeting
Zoom Meeting ID
Dirk Duellmann
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Join via phone
Zoom URL

Present: UIrich (Chair), Matthias


Action items last meeting:

  • Check if the CERNLIB 2022 sources could be put alongside with the CERNLIB2006 sources on https://cern.ch/cernlib  [Geraldo] :
    • Done, one version only though
    • Shall up update the landing page ?
    • What is the ownership of the page now ? 
  • Check if the CERNLIB 2022 CI artifacts  can be automatically pushed to /cvmfs/sft.cern.ch [Geraldo]  
    • Pending
  • CERNLIB short writeup is missing on CDS [Ulrich]
    • Done
  • Matthias reported about issues reading RZ files in CC7 in the OPAL code while it works just fine in CS8 (32bit). It was suggested to open a ticket as this is not observed by DELPHI [Matthias]
    • This will not be followed up for now as it works fine for CS8. Done
  • Circulate link to the ACAT poster draft [Andrii]. Feedback welcome ! Done


  • Building on MAC
    • Marcello reported on MM to have issues with gfortran on his MAC
    • Matthias opened a ticket (issue 28) about a failed test in ffkey which segfaults. He will try to run this in a debugger to see where this happens

Status update:

    • Added a free branch with FLUKA routines replaced by dummies
    • Added 2 new tags, one for the free version and one for non-free
    • The way to track the versions is via those tags
    • Marcello reported that there is interest to test CERNLIB from an external collaborator. A working MAC build would be required for this
    • Improved CI
    • Event display pimped up, adding hard copy function (as .tga) and support for transparency
    • Added the c++ analysis framework to development versions on /cvmfs/delphi.cern.ch/32bit and /cvmfs/delphi.cern.ch/64bit
    • Pushed new development versions as build from the CI
    • OpenData initiative for DELPHI produced first samples (for educational purpose only) as CSV and root ntuple files
  • OPAL:
    • Evaluation efforts ongoing
    • Issues building on MAC, see above (failed test in ffkey)


  • OPAL 64bit: this was tried in the past with some success. 
    • This was either based on 64bit CERNLIB builds from /cvmfs/sft.cern.ch/lcg/external/cernlib/2006a or a Fedora build (including Debian patches) which existed on a previous  version of lxplus at the time
    • It would be nice to re-try with cernlib 2022
  • Validation: Ulrich reported that when dumping event data for different versions or on different platforms he observes differences in individual tracks of the order of 10^-6. This is most likely to be expected as quite some code is rerun (both for OPAL and for DELPHI) inside the frame works. We believe that we have to live with this.
  • Ulrich showed interest in checking the OPAL event display using OpenPhigs. Matthias will check for the sources.

Action items:

  • Check MAC builds of CERNLIB issues (Matthias, Marcello, Andrii). Matthias mentioned that MAC is a fast moving target
  • Ownership of cern.ch/cernlib needs more clarification (Geraldo ?)


There are minutes attached to this event. Show them.
    • 11:00 AM 11:05 AM
      Introduction 5m
      Speaker: Ulrich Schwickerath (CERN)
    • 11:05 AM 11:25 AM
      Community CERNLIB status update 20m

      Recent changes, licensing

      Speaker: Andrii Verbytskyi
    • 11:25 AM 11:35 AM
      ALEPH 10m
      Speaker: Marcello Maggi (Universita e INFN, Bari (IT))
    • 11:45 AM 11:55 AM
      OPAL 10m
      Speaker: Matthias Schroeder (CERN)