vdas_20120315
Special VDAS-DAQ meeting about advanced Virgo upgrade - DAQ TDR + Virgo computing models
1. Upgrade of:
- Concurrent Versioning System: CVS to be replaced by SVN? git? XXX?
- Configuration Management Tool: CMT to be replaced by CMake? XXX?
- Software development models:
- library release - code freeze
- virgoDev-virgoApp management
- rules for online vs rules for DA software
- installation of DA software in CC + LSC clusters
- ...
- Platform migration to Scientific Linux 6 / 7?
2012/03: Proposal for a new Virgo Package Installation (from virgoDev to virgoStaging)
2012/03 - Ideas about CVS/SVN, CMT/CMake, management of external packages, SL6/SL7
Gary, Martin, Giulio, Emmanuel, Didier, Benoit, Alberto, Franco, Elena, Alain, Loic, Alain, Cristiano,
1/ VirgoDev-VirgoApp management:
virgoDev is not controlled and has always been a mess and a source of problems in the end for software development. Emmanuel and Franco are proposing:
a/ to suppress virgoDev. Developments are made in users' homes.
b/ to have a VirgoStaging zone where packages will be *installed* to perform test of integration before the final installation in /virgoApp. This zone is meant not to be a developing zone. Packages can only be installed not modified. To do that, a special script will be used to install from CVS the packages.
MAB expressed concerns that virgoStaging would become quickly the virgoDev mess if everyone can make modification there. MAB is not convinced that this /virgoStaging is really useful.
Giulio and Elena expressed concerns that they may need to do modifications in packages in /virgoStaging.
Discussion about sCVS: MAB repeats that she is against the fact that sCVS becomes a reference. sCVS si not CVS compliant, so the script to install software in virgoStaging must be free of sCVS. Franco agress that the script only needs to do cvs checkout.
Decision: will try to enforce strict policy for this new zone and make virgoDev disappear
2/ Tools upgrade:
a/ CVS is obsolete. git is too different from CVS and a bit too cumbersome for Virgo use. A good candidate would be SVN. Has all CVS features and brings nice new features (web access, revision id for package, add/remove directory ...). General consensus about :
- the CVS archive history must be kept. Tools exist to do that.
- the transition CVS -->SVN could be prepared right now. Link with CMT. A priori newest version of CMT provides SVN plugins.
sCVS layer: could be adapted with SVN. MAB again mentioned that now Virgo users should be "educated" enough with such tools to use native commands. Franco agrees! Didier finds scvs very useful. Franco will see, but admits that CVS/SVN native commands are the rules!
b/ CMT: CMT is still supported but there is no more large developments, which is a problem as new features would be very usefull. For instance CMAke has features for the installation or rpms production that would be very useful for Franco. On the other hand, CMT is found very useful by Virgo developers and the migration to another tool would not be as easy as the transition CSV --> SVN. Franco proposed to have an automatic way to generate from the requirements the file useful for CMake that he could use for pacakge management. MAB: developers could switch to Cmake and the concurrent use of CMT and CMake could generate troubles.
Discussion about autotools used widely in the open software community: would help the interoperability with the LSC software. But the LSC software management does not correspond to our needs and requirements. Autotools would pose more problems than bringing advantages.
Concensus: there would be advantages to replace CMT by another tool, but this cannot be done without investigations. Franco will continue his investigations around CMake. Franco reminds us that LHC experiments have done the transition in the past. Not impossible!
c/ external packages question:
Emmanuel has proposed that the CMT external packages be replaced with packages containing the extrenal package. Drawback : size of the packages & size in the archive. Idea: have the choice to install the CMT wrapper package or the "Full" package. We have not concluded. Both solutions have pros and cons.
Conclusion: Loic will update the DAQ TDR chapter. MAB will send a draft of the computing model in the next weeks.
Next weekend with remaining items in 2 weeks.