DELPHI data preservation activity
Changes since 2002
Many years after the end of the experiment IT services are changing, and the software stack has to adapt to that to ensure the continued accessibility of the DELPHI data. Changes in services include:
At the same time new services have arrived which replace the functionality of these disappearing services.
- With CentOS7 the Fortran compiler g77 will finally disappear and is replaced by gfortran.
- Support of LSF is stopped at the end of 2017.
- The role of CASTOR has changed. RFIO clients (like rfcp) are gone.
- AFS is being phased out.
- old binaries no longer work due to change in glibc. This affects in particular GPHIGS which is used for DELGRA
- EOS is taking over functionality from CASTOR and AFS
- HTCondor is replacing LSF
- CVMFS has turned up with allows for world-wide read-only sharing of software. It is available at all GRID sides.
New DELPHI software stack
Based on the software CD created in 2002 a new software stack has been created. It is the default on CentOS7 (eg. lxplus7.cern.ch), and is also available for testing on SLC6 (lxplus).
The new software stack has no remaining dependencies on AFS, LSF or CASTOR. It should work fine outside CERN as well. Currently, the following operating systems are supported:
- All DELPHI data has been copied from CASTOR to EOS. On lxplus and lxbatch it can be directly accessed from /eos/experiment/delphi. The CASTOR tape copy (2 copies) remains intact for archiving and disaster recovery.
- The default compiler has been changed to gfortran. All libraries have been recompiled using this version.
- The sources of the main components of the software stack have been transfered to https://gitlab.cern.ch/delphi
- Thanks to the help of the DPHEP initiative, OPAL and the CERN IT department we now have updated libraries for GPHIGS. DELGRA is fully functional again on both lxplus and lxplus7.
- DELPHI libraries are available on /cvmfs/delphi now
These tags are created from the output of the command "lsb_release -a".
- ScientificCERNSLC-6 (SLC6). This is compatible with SL6.
Using and testing
On Centos7 (eg lxplus7.cern.ch) the new software stack is the default. On lxplus you can test it by manually sourcing /cvmfs/delphi.cern.ch/setup.sh or /cvmfs/delphi.cern.ch/setup.csh, depending on your shell.
You may need to review your local settings.
Caveats and things still to be done
Tasks still to be performed are tracked in the DPHEP JIRA task tracker. Input to any of the tickets is very welcome. Some remarks (as of Nov. 2017):
- The only remaining AFS dependency of the software stack left is related to the GPHIGS license file which is restricted to CERN nodes. If you want to run DELGRA outside CERN you have to buy a GPHIGS license. See https://gitlab.cern.ch/delphi/delgra for any details.
- A large part of the documentation is still on AFS, specifically internal notes, theses etc.
- DELPHI web pages are still hosted on AFS. They need to be moved to /eos
- It would be nice to add some more complex sample analyses to the new stack.
At this point in time it is very difficult to do meaningful in depth tests of the stack. If you use it please do cross checks with old archived data if possible, and report any problems to email@example.com
Links and references
Last modified: Tue Nov 21 09:24:37 CET 2017