LHC Computing at RAL PPD Dave Newbold RAL PPD / University of Bristol The LHC computing challenge PPD and the Grid Computing for physics PPD added value

Audit 2007: 18th September orders of magnitude The SM Higgs All interactions Single p-p beam crossing event The LHC Computing Challenge Search for rare events vs huge statistical background LHC dataset ~ 5 Petabytes / yr Completely new computing regime

Audit 2007: 18th September Meeting the Challenge Scale of the problem –The largest scientific computing project in history – by far –Outstrips capabilities of any one institute, technically and politically –Computing now a worldwide activity, away from the accelerator lab A new approach to computing –The Grid: key enabling technology for 21st century HEP computing –Enables remote large computers as ‘generic utilities’ - securely –Coordinated through the CERN-sponsored LCG project The computing system –Built on a backbone of ~10 internationally-recognised ‘Tier-1 centres’ Safeguard the raw data, process on demand, serve to physicists –RAL Tier-1 caters for all four major LHC experiments (most do not) –University groups (~15 in the UK) typically provide ‘Tier-2 centres’

Audit 2007: 18th September PPD Computing Strategy Goals for LHC computing: –Support the UK LHC programme with large-scale computing resources –Develop and support the basic LHC computing infrastructure –Maintain expertise, and experts, in modern computing / software –Provide leadership / coordination for UK HEP computing Practical deliverables: –Tier-1 centre : supporting the international LHC community –Local (Tier-2) computing resources for UK physics analysis –Leadership and coordination of international Grid projects Including technical role in Grid software development –Leadership of LHC experiment computing and software projects –Interface between LHC experiment and computing resource providers Ensuring that generic resources are useful for physics These goals are addressed most effectively by the UK national lab

Audit 2007: 18th September PPD in the GridPP Project UK National Grid effort –2000: UK HEP community proposes a collective computing project PPD provided initial stimulus and leadership for this effort –The resulting GridPP project is now entering its third phase ~ £70M PPARC / EU funding over ten years –GridPP is a leading partner in all areas of LHC computing PPD role –The leading contributor to the project from the start –Project Management Board 50% RAL (18 seats, 5 PPD, 4 e-science) Chair of Deployment Board (D. Kelsey) Chair and Associate Chair of User Board (G. Patrick, D. Newbold) Grid Middleware coordinator (R. Middleton) Documentation officer (S. Burke) PPD gives a stable, neutral focal point of the project –Brokers, and enables, the technical contributions of UK institutes

Audit 2007: 18th September GridPP in Context PPD has a central role in every one of these areas

Audit 2007: 18th September Grid Research: Highlights International Grid middleware projects –‘Grid machinery’ is largely provided by EU-funded software projects –PPD is the contact point for Euro projects, GridPP, UK HEP community –Working on concrete software deliverables, usable beyond HEP (S. Fisher et al) Scalable monitoring tools – vital component of realistic Grid architecture Security and policy –The real ‘machinery’ behind the Grid is political Brokering and agreeing sharing of ‘foreign’ resources worldwide –PPD has led construction and agreement of worldwide security policy Also works on Grid security at a practical hands-on level Deployment –The art and science of making a huge dispersed system work –A PPD history of ‘young guns’, with strong international profile Expertise directly supports the LHC physics effort (S. Burke, S. Traylen) PPD is a highly effective environment for (senior) computing specialists –Lab’s international reputation allows us to take a early role in new projects –PPD can support and facilitate career development in specialist areas

Audit 2007: 18th September Expt. Computing: PPD Role Physicists’ view of the Grid –“How can it help me extract results, make discoveries?” –PPD key role is to make the system useful for physics – pragmatically The ‘missing pieces’ –Grid is a generic system; must be adapted, customised for physics –Requires interfaces, documentation, physicist-oriented tools E.g. physically meaningful cataloguing / description of data –Need people with expertise in both physics and modern computing Scientists, working directly within the experiments Computing for physics –Tier-1 / 2 centres are a generic resource - need operators / support Senior ops / support staff are trained physicists (C. Brew, M. Bly) –PPD provides the ‘glue’ that makes the centres work for physics UK confident that the RAL Tier-1 will deliver, come what may –Demonstrated success of (first) BaBar Tier-A centre (T. Adye, C. Brew)

Audit 2007: 18th September Expt. Software: Highlights Joint LHCb / ATLAS ‘Grid user interface’ tool - a “GridPP product” –UK coordinator is a PPD physicist (G. Patrick); >800 real users internationally –This is how most people will do physics on a day-to-day basis Job details Logical Folders Job Monitoring Log window Job builder Scriptor

Audit 2007: 18th September Expt. Operations: Highlights CMS CSA06 (Computing, Software, Analysis) - D. Newbold computing model steer –A non-stop month-long test of the realistic data flows, processing –All did not go according to plan (of course); RAL / PPD flexibility tested

Audit 2007: 18th September Summary Wide portfolio of LHC computing activity –Original, world-class, research in new computing techniques –Organisation, leadership of Grid research, and computing for physics –Practical delivery of computing resources, useful for physics The PPD role –A focal point for LHC computing, inside and outside the UK –A welcome collaborator for Universities, facilitates UK Grid research PPD added value –Contact point for physicists, e-science specialists, resource providers –The interface to large-scale facilities, providing access for UK HEP –A ‘trusted partner’ in international computing, representing the UK –A critical mass of recognised computing / software expertise The real work starts now! –PPD role will become ever more vital as we approach LHC start-up