LHC Data Analysis using a worldwide computing grid OSG Consortium Meeting Gainesville 23 January 2006

WLCG Purpose and Collaboration Develop, build and maintain a distributed computing environment for the storage and analysis of data from the four LHC experiments Ensure the computing service … and common application libraries and tools Phase I – 2002-05 - Development & planning Phase II – 2006-2008 – Deployment & commissioning of the initial services WLCG Collaboration ~100 computing centres around the world 12 large centres (including FNAL, BNL) ~30 federations of smaller “Tier-2” centres Memorandum of Understanding Agreed in October 2005, now being signed Resources Commitment made each October for the coming year 5-year forward look

LCG Service Hierarchy Tier-0 – the accelerator centre Data acquisition & initial processing Long-term data curation Distribution of data  Tier-1 centres Canada – Triumf (Vancouver) France – IN2P3 (Lyon) Germany – Forschunszentrum Karlsruhe Italy – CNAF (Bologna) Netherlands – NIKHEF/SARA (Amsterdam) Nordic countries – distributed Tier-1 Spain – PIC (Barcelona) Taiwan – Academia SInica (Taipei) UK – CLRC (Oxford) US – FermiLab (Illinois) – Brookhaven (NY) Tier-1 – “online” to the data acquisition process  high availability Managed Mass Storage –  grid-enabled data service Data-heavy analysis National, regional support Tier-2 – ~100 centres in ~40 countries Simulation End-user analysis – batch and interactive

CPU Disk Tape

LCG Service Deadlines full physics run first physics cosmics 2007 2008 2006 Pilot Services – stable service from 1 June 06 LHC Service in operation – 1 Oct 06 over following six months ramp up to full operational capacity & performance LHC service commissioned – 1 Apr 07

LCG depends on two major science grid infrastructures EGEE - Enabling Grids for E-Science OSG - US Open Science Grid

Baseline Services Operated by Centres according to VO and Tier - Storage Element – SRM -- dCache, DPM, CASTOR, HPSS - Basic transfer tools – Gridftp, srmCopy. - Reliable file transfer service – within the VO – all Tier-1s must make data available to all other Tier-1s and to all Tier-2s - Catalogue services – LFC, Globus RLS - Catalogue and data management tools – lcg-utils - Compute element – Globus/Condor-G based CE  Condor-C based CE - Workload management – -- EGEE Resource Broker, and other solutions -- Operated as services at specific sites -- compatibility with the standard CE is required - VO agents – prototyping phase – workshop this week in Amsterdam - VOMS. - Database services - POSIX-I/O - Application software installation - Job monitoring tools - Reliable messaging service - Information system http://lcg.web.cern.ch/LCG/peb/bs/BSReport-v1.0.pdf

Optical Private Network Wide Area Network T2 T2 T2 T2 T2s and T1s are inter-connected by the general purpose research networks T2 T2 T2 GridKa T2 IN2P3 10 Gbit links Optical Private Network TRIUMF Any Tier-2 may access data at any Tier-1 T2 Brookhaven ASCC Nordic T2 Fermilab RAL CNAF PIC T2 T2 SARA T2 LCG T2

Sustained Data Distribution Rates CERN  Tier-1s Centre ALICE ATLAS CMS LHCb Rate into T1 MB/sec (pp run) ASGC, Taipei X 100 CNAF, Italy 200 PIC, Spain IN2P3, Lyon GridKA, Germany RAL, UK 150 BNL, USA FNAL, USA TRIUMF, Canada 50 NIKHEF/SARA, NL Nordic Data Grid Facility Totals 1,600

Service Challenges Purpose Understand what it takes to operate a real grid service – run for days/weeks at a time (not just limited to experiment Data Challenges) Trigger and verify Tier1 & large Tier-2 planning and deployment – - tested with realistic usage patterns Get the essential grid services ramped up to target levels of reliability, availability, scalability, end-to-end performance Four progressive steps from October 2004 thru September 2006 End 2004 - SC1 – data transfer to subset of Tier-1s Spring 2005 – SC2 – include mass storage, all Tier-1s, some Tier-2s 2nd half 2005 – SC3 – Tier-1s, >20 Tier-2s –first set of baseline services Jun-Sep 2006 – SC4 – pilot service  Autumn 2006 – LHC service in continuous operation – ready for data taking in 2007

Service Challenge 3 Throughput Tests

Tier-3s and Opportunistic Resource Usage Tier-3s - Physics Departments, private systems Private analysis, simulation Need easy access to all VO Tier-1s, Tier-2s on EGEE and OSG – -- job submission, data retrieval Simulation – opportunistic resource usage on the grid By carefully limiting the requirements needed from the environment -- LHCb has been very successful on the EGEE grid Standard job submission, storage interfaces essential

Conclusions NOT an option to get things going later LCG depends on two major science grid infrastructures – EGEE and OSG  inter-operability and standards very important Job management, storage interfaces, data transfer Tier-1 and Tier-2 centres – For components where compatibility is essential baseline services are defined which can be deployed on OSG and EGEE The Service Challenge programme this year must show that experiments can operate across the different grid infrastructures Stable, reliable services By the end of September the underlying grid services must be in continuous, stable operation First data will arrive next year We must have an integrated and reliable service well ahead of the first beams NOT an option to get things going later