240 likes | 377 Views
Computing at LHC. Hiroshi Sakamoto International Center for Elementary Particle Physics, the University of Tokyo. Contents. LHC Atlas Experiment Computing Requirements ATLAS Computing Model Distributed Analysis on a Data Intensive Computing Grid Worldwide LHC Computing Grid Project
E N D
Computing at LHC Hiroshi Sakamoto International Center for Elementary Particle Physics, the University of Tokyo
Contents • LHC Atlas Experiment • Computing Requirements • ATLAS Computing Model • Distributed Analysis on a Data Intensive Computing Grid • Worldwide LHC Computing Grid Project • Computing System Commissioning • Grid Technology: Can be a Common Solution for Future High Energy Physics Programs?
LHC Atlas Experiment • LHC – Large Hadron Collider • Atlas – A Toroidal LHC ApparatuS
CERN Council looks forward to LHC start-up (CERN Press Release, June 20th, 2008) “The accelerator, detectors and computing are all on course,” said CERN Director General Robert Aymar, “and we are looking forward to the earliest possible LHC start-up.”
Installing the beam pipe at the ATLAS experiment on 16 June: the final section of the LHC. Once all sectors are cold, electrical testing will be concluded in readiness for first beams, currently scheduled for August.
Computing Requirements • Basic Parameters
Input Parameters Reconstruction: 15kSI2ksec/event – 3000kSI2k (200Hz) Simulation: 400kSI2ksec/event – 4000kSI2k (10Hz)
Atlas Computing Model • Tier Model ~ Hierarchy • Tier0: CERN • Tier1: Quasi-Online Data Center • Tier2: National/Regional Analysis Center • Tier3: Department Facility • Tier4: User Desktop • Tier0 ~ Tier2 are operated under MoU
Distributed Analysis on Data Intensive Computing Grid • Data Grid ( Data Intensive Computing Grid ) • Building Blocks • Authentication/Authorization • Workload Management • Distributed Data Management • Information/Monitoring/Accounting
Authentication/Authorization VO (Virtual Organization) – Roles – Groups
Workload Management Sophisticated Match Making Massive Job Subscription
Distributed Data Management Storage resource allocation Efficient and reliable file transfer
Worldwide LHC Computing Grid Project • Collaboration Body • Contribution to LHC Experiments • Memorandum of Understanding in the framework of WLCG collaboration • Federated Grids • EGEE/gLite • OSG • NorduGrid
CPU(MSI2k-days) Tier1 Disk(TB) Tier1 Tape(TB) Tier1
Computing System Commissioning • Full Dress Rehearsal • Full scale test using simulated data • Combined Computing Readiness Challenge (CCRC08) • Simultaneous operation of 4 experiments
Grid Technology: Can be a Common Solution for Future High Energy Physics Programs? • Technical Point of View • Scalability ~ O(100) sites, O(100k) CPU, O(10PB) disk, O(100k) jobs/day, O(10M) files, O(10GB/s) transfer, O(10k) users, O(100) VOs • Minimum functionality for HEP experiments • Still needs high operation cost ~ manpower • Collaborative Point of View • Accessibility ~ Equivalent to all collaborators • Global infrastructure ~ Communication! • Political/Financial Point of View • Visibility ~ Recognized in your institute/country • You must/can provide your own resources
But, you already have… Eric Yen, ISGC08