1. AliRoot survey P.Hristov 11/06/2013

2. Offline framework  AliRoot in development since 1998  Directly based on ROOT  Used since the detector TDR’s for all ALICE studies  Few packages to install: ROOT, AliRoot, Geant3, AliEn client  Optionally use Geant4 or Fluka instead of Geant3 => additional VMC package  Optionally DATE + AMORE for DA and DQM development  Optionally FASTJET + Boost + CGAL for jet studies  Works on Linux & Mac OS  Integration with DAQ (data recorder) and HLT (same code-base)  Abstract interfaces and “restricted” subset of C++ used for maximum portability  Used for simulation, reconstruction, calibration (detector algorithms), alignment, quality assurance, monitoring, and analysis 2

3. AliRoot: some statistics 3  Total Physical Source Lines of Code (SLOC) = 3,437,986  C++: 2589313 (75.31%)  Fortran: 818387 (23.80%)

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6. AliRoot: Framework, Detectors & Analysis 6  Report Period: 1999-05-18 to 2013-06-09  Total Files: 7826  Total Lines of Code: 2544289  Developers with commit rights: 181 Framework & Detectors Analysis PWG’s reorganization

7. 7 AliRoot: some statistics

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9. Releases and Analysis Tags 9  Releases:  Release branches every 6 months  First “stable” tag about two weeks after the creation of a branch  Weekly tags to address the porting requests  Extensive local tests, not always able to detect the problems  Real production quality – at the end of the release lifetime  Many porting requests to solve issues or to provide updated functionality  Analysis tags  Twice a week, sometimes more often  Adopt new Root versions only after a test with the same analysis tags

10. v5-03-Release: porting requests 10

11. AliRoot survey: Motivation 11  AliRoot is a big project with many contributors. A survey provides  Structured feedback  Opportunity for “direct democracy”  Almost immediate responses  Goals for such survey  evaluate the current AliRoot state  identify important issues  search for possible improvements  get ideas for redesign/refactoring  provide input to the CWGs and O 2  update the offline plans

12. AliRoot survey: preparation 12  Free and powerful survey tool: www.limesurvey.orgwww.limesurvey.org  Installed @acid.cern.chacid.cern.ch  Several iterations to tune the questions and the survey logics  It took much longer to prepare the survey…  Next time we will try more professional approach

13. Survey: who are we? 13  What is the level of your programming experience?  Inexperienced. I have only basic knowledge of C++: 0.74%  Less experienced. I have taken some programming course, but most of my understanding comes from ROOT tutorials. I wrote code/scripts to get results and copy/paste code snippets in order to reuse them: 8.15%  Experienced. I know couple of programming languages well (C++/Fortran). I know what Object Oriented code is. I frequently re- use my own code with minor modifications: 25.93%  Very experienced. I have more than 5 years experience in at least two programming languages (C++/Fortran). I know what Object Oriented code is and how to write it. I have contributed several classes to AliRoot. I profile the CPU and memory consumption of my code: 31.11%  Expert. I am very experienced and I have contributed significantly to the AliRoot framework: 8.15%

14. Level of your programming experience 14 InexperiencedLess experienced ExperiencedVery experiencedExpert

15. Familiarity with C++ 15

16. Familiarity with Root 16

17. AliRoot experience and fields of interest 17  How long have you been using AliRoot? 7.6±4.0 years Other: Trigger Grid Technologies, Distributed Computing

18. Where do you most commonly use ROOT/AliRoot when performing intensive computing tasks? 18

19. Comments on the way to run CPU-intense tasks 19  Own computer to develop then PROOF/grid to analyze data. I also use batch systems directly for testing / local productions  Would need to tick more than one option: desktop/laptop, batch system, GRID  Simulation on Grid, analysis on SAF...  On my desktop/laptop AND on the GRID  I have been also using a batch system for years for analyses that did not need to access ALICE data (e.g. simulations). I used CAF for analyses that need to run on small data samples  I also use CAF very extensively, but for computing tasks, I prefer the Grid  I am not an AliRoot user

20. Conclusions from the general section 20  AliRoot is big project with many experienced developers and users  After 15 years of existence AliRoot is still under active development  The accent moved from framework & detectors to development of analysis code  GRID > local > CAF for computing intensive tasks