BaBar & Grid Eleonora Luppi for the BaBarGrid Group TB GRID Bologna 15 febbraio 2005

15/02/2005 TB INFN-GRIDEleonora Luppi SPGrid Simulation Production (SP) in BaBar is a typical distributed effort. We decided to give SP a priority higher then to other kinds of BaBar software on Grid SP needs a lot of CPU time, a little input, standard output BaBar MonteCarlo event simulation makes use of Objectivity Database for conditions and Xrootd for trigger background

15/02/2005 TB INFN-GRIDEleonora Luppi BaBar SPGrid In Italy full grid approach

Eleonora Luppi Resources LCG middleware About 200 shared CPUs used for production tests AMS and Xrootd servers installed in Ferrara, Naples and Padua ProdTools installed on User Interface in Ferrara BaBar Resource Broker in Ferrara 15/02/205 TB INFN GRID

Eleonora Luppi Production scheme /02/205 TB INFN GRID

Eleonora Luppi Software Installation Simulation Software packaged and installed on involved sites Package distributed and tagged using LCG tools: – ManageSoftwareTool (submitted like a standard job) – Transfer packages from closest SE to WNs – Run scripts to install the simulation software – lcg-ManageVOTag Main script – Set all variables needed – Run Moose – Compress and transfer output to the SE ProdTools – spsub integrated with standard Grid submission – Output retrievied from SE to UI using a custom script – spmerge integrated in standard Grid submission (test in progress) 15/02/205 TB INFN GRID

Eleonora Luppi SP on INFN Grid Future Plans Add CNAF pool resources Add specific BaBar resources (trigger and Cdb servers) at least at CNAF site Add other Babar-Grid site Gridify BaBar resources on Italian Tier 1 Start true production on the “Grid Farm” Coordination with other national Grid sites

15/02/2005 TB INFN GRID Eleonora Luppi Future in UK Started rolling reinstalls of the UK farms with SL All BaBar UK Farm site are also GridPP Tier 2 sites New LCG installation methods means we can add LCG with minimal changes on our farms Overlap of work done between UK-SPGrid and Grid.It SP is quite small Rewrite submitter to: – Submit grid.it style jobs and “full install” jobs (or merge these so Job choose appropriate type when it runs) – Probably do it in python to make use of native edg-job-* commands – Abstract the submit function so we can use other Grids Rewrite unpacker to: – Unpack Grid.It jobs – Do it in parallel Rewrite monitoring to monitor LCG Jobs C.Brew

Eleonora Luppi SPGrid status and plans in Canada 15/02/2005 TB INFN GRID

Eleonora Luppi “Analysis” Grid “Analysis” in the following means any kind of experimental data processing Problems to face: – Large amount of data to analyze – Remote access to input data – Different kinds and sizes of output depending on the type of analysis A step by step approach can be useful to reduce the complexity of the problem 15/02/2005 TB INFN GRID

Eleonora Luppi Skim Production in the Grid – Outline Short definition: GRID = Submit a job locally and run it anywhere. Submit skim jobs from a central site (SLAC) Check job requirements and run the job at an appropriate Tier-site (or SLAC) Move job output to the pre-defined output area (~ MB/job) Import collection to be skimmed. Skim Operator Site Manager Merge will be done locally at SLAC! W. Roethel 15/02/2005 TB INFN GRID

Eleonora Luppi Site Requirements Software release has to exist. Conditions database has to exists. Input collection has to be available. Local worker nodes need to have means to move data to remote locations using WAN (e.g. using Grid Middleware). W. Roethel Similar to SP 15/02/2005 TB INFN GRID

Eleonora Luppi “Analysis” Summary Step by step approach for the analysis Skimming seems to be a good starting point We need to study data handling possibilities to obtain an efficient and simple way to handle and maintain data, also in non-BaBar sites Results of tests with grid-analysis special infrastructures (see Alien and children) tell us that they can be interesting but need more support and stability 15/02/2005 TB INFN GRID

15/02/205 TB INFN GRIDEleonora Luppi BaBar on INFN Grid Future Plans Use of CNAF pool resource for SP: BaBar quota (50 machines) and the common when available Install soon a Cdb (Objectivity) and a Background trigger (Xrootd) server at CNAF, on private BaBar resources Add other Babar-Grid sites (Torino is going to have resources for Cdb and Bckgrnd triggers) Gridify BaBar resources on Italian Tier 1, to reach asymptotically a common use of CNAF resource (but we need to maintain “traditional” account on BaBar analysis farm during 2005) Use of dedicated BaBar machines at CNAF for merging SP data before sending them to SLAC We need at least 2 TB of buffer at CNAF SE for merging SP data (BaBar disk space at CNAF is 34 TB, including IBM and SE) When ready, skimming will need at least CPU and a buffer for skimming and merging real data of about 4-5 TB.

Eleonora Luppi Conclusions SPGrid is a reality for true SP production We will converge to a common European solution soon (in the mean time we will run SP jobs using the national Grid facilities) Our next goal is to have an Analysis Grid capable of running “standard” analysis programs (i.e. Skimming) We need to give special attenction to data handling tools 15/02/205 TB INFN GRID