Interfacing Grid-Canada to LCG M.C. Vetterli, R. Walker Simon Fraser Univ. Grid Deployment Area Mtg August 2 nd, 2004

M.C. Vetterli; SFU/TRIUMF The Canadian Model  Establish a large computing centre at TRIUMF that will be on the LCG and will participate in the common tasks associated with Tier-1 and Tier-2 centres.  Canadian groups will use existing university facilities (or what they will become) to do physics analysis. They will access data and the LCG through TRIUMF.  The jobs are smaller at this level and can be more easily integrated into shared facilities. We can also be independent of LCG middleware. In this model, the TRIUMF centre acts as the hub of the Canadian computing network, and as an LCG node

TRIUMF Gateway cpu/storage Experts - MC data - ESD’ - calibration - access to CDN Grid - algorithms - calibration - MC production - access to ATLAS Grid - AOD - DPD - technical expertise The ATLAS-Canada Computing Model CA*Net4 USA, Germany, France, UK, Italy, … CERN ATLAS Grid Canadian Grid - ESD - access to RAW & ESD UVic, SFU, UofA, UofT, Carleton, UdeM(CFI funded)

M.C. Vetterli; SFU/TRIUMF What are we doing now?  Participate in Data Challenges  Prototype the TRIUMF centre  Establish LCG centres in Canada: TRIUMF, Alberta, Toronto, Carleton, and Montreal are all working  Set up a Canadian Grid test-bed (Grid-Canada PG1)  Develop middleware to interface between GC-PG1 and LCG

M.C. Vetterli; SFU/TRIUMF Federated Grids for ATLAS DC2 Grid-Canada PG-1 WestGrid LCG/WestGrid SFU/TRIUMF LCG/Grid-Can LCG In addition to LCG resources in Canada

M.C. Vetterli; SFU/TRIUMF Linking HEPGrid to LCG..... GC Res.1 GC Res.n Grid-Can negotiator/ collector WG UBC/ TRIUMF TRIUMF TRIUMF cpu & storage lcgce02: Condor-G lcgce01 LCG BDII/RB/ scheduler Class ad 1) Each GC resource publishes a class ad to the GC collector 3) The TRIUMF information provider aggregates this info into a single resource Class ad 2) The same is done for WG 3) The CondorG job manager at TRIUMF builds a submission script for the TRIUMF Grid 4) The GC negotiator matches the job to GC or WG 1) The LCG RB decides where to send the job (GC/WG or the TRIUMF farm) Job class ad 2) Job goes to the TRIUMF farm or GC decides to send the job to WG 5) The job is submitted to the proper resource MDS 4) TRIUMF passes this information on to LCG through CE02 5) TRIUMF also publishes its own resources separately through CE01  Load balancing GC decides to send the job to its own resources

M.C. Vetterli; SFU/TRIUMF Summary  Canada is participating in LCG through “normal” LCG sites  We have also integrated the Grid-Canada test bed through a separate CE at TRIUMF  The Grid interface uses Condor-G to re-submit LCG jobs  The interface has been fully tested and has now been running in production for a few days  Rod Walker will now give more technical details