1. User requirements and use-cases JRA4 Face-to-Face Meeting – CERN 16 June 2004 Paul Mealor, UCL

2. JRA4 F2F Meeting – CERN – 16 June 2004 - 2 Sources of information LCG: Ian Bird (not really) NA4 people: Frank Harris (HEP)  Nick Brook (LHCb)  Roger Jones (Atlas)  Dave Newbold (CMS) Johan Montagnat (Biomed) NA4 documents Combined requirements from EDG Biomedical requirements They have use-cases, somewhere Peter Kunszt, Peter Clarke… GHPN

3. JRA4 F2F Meeting – CERN – 16 June 2004 - 3 HEP use cases Based around replica management Two main overview use-cases: User job submission  Middleware?  User requires a job to be done as quickly as possible Data reprocessing  Operations? Middleware?  Large number of jobs  Time-limited data reprocessing  Time-limited data transfer Probably also useful for Task 2 use-cases

4. JRA4 F2F Meeting – CERN – 16 June 2004 - 4 LCG Data Scheduler

5. JRA4 F2F Meeting – CERN – 16 June 2004 - 5 NA4 combined requirements Selection of requirements R3.11 Data access cost estimation  Yes yes R2.2 Parallel jobs execution  Requires MPI, can we do anything about this? R2.4 Multiple data jobs  Lots of similar data sets  Retrieved from the same place at the same time  Summed costs alter the optimisation scenario R2.6 Interactive Jobs  CLI, GUI, image manipulation, job steering?  Need low RTT, low jitter, minimum BW?  Time constrained – the user has to be there to use the job  Data required for user’s sites, as well as for CE/SE sites   Task 2 requirements, also R2.10 Job killing

6. JRA4 F2F Meeting – CERN – 16 June 2004 - 6 NA4 Biomedical use-cases Two pilot applications GATE Monte-Carlo simulation Based on GEANT4 Basically the same as HEP Monte-Carlo jobs GPCALMA Automatic analysis of mammographs Distributed data (mammographs stored at local hospitals) Distributed analysis  Pretty much ordinary job submission Interactive inspection  Could be interesting  Images are only 10MB Plus Content-based query of medical image databases Remote interactive segmentation algorithm (2 updates / s)

7. JRA4 F2F Meeting – CERN – 16 June 2004 - 7 GHPN use-cases GGF Grid High Performance Networking Working Group Mark Leese, Tiziana and I have been writing some use- cases for them Administrative interaction with monitoring systems HEP job submission Cost-estimation use-cases Aimed at API design Still useful for us Continues in parallel with JRA4 work

8. JRA4 F2F Meeting – CERN – 16 June 2004 - 8 Future work NA4 open meeting Much more info from HEP applications Much more info from biomed pilot applications Questionnaire/requirements template Fill in for current use-cases Extend the questions