26 Nov 1999 F Harris LHCb computing workshop1 Development of LHCb Computing Model F Harris Overview of proposed workplan to produce ‘baseline computing model for LHCb’

26 Nov 1999 F Harris LHCb computing workshop2 WHY are we worrying NOW about this? zHOFFMAN REVIEW (starting Jan 2000) yHow will the LHC experiments do their computing? Answers in late 2000 xThe basic logical data flow model, patterns of use, resources for tasks xThe preferred distributed resource model (CERN,regions,institutes) yComputing MOUs in 2001 zCountries (UK,Germany, …) are planning now for ‘development’ facilities

26 Nov 1999 F Harris LHCb computing workshop3 Proposed project organisation to do the work Tasks and Deliverables(1) nLogical data flow model (all data-sets and processing tasks) èData Flow Model Specification nResource requirements èData volumes,rates,CPU needs by task (these are essential parameters for model development) - measure current status and predict the future èURD giving distributions nUse Cases èmap demands for reconstruction, simulation, analysis, calibration and alignment onto the model (e.g. physics groups working) èDocument ‘patterns of usage’ and resulting demands on resources - ‘workflow specification’

200 kB100 kB 70 kB 0.1 kB 10kB 150 kB 0.1 kB 200 Hz LHCb datasets and processing stages (must update CPU and store reqts.)

26 Nov 1999 F Harris LHCb computing workshop5 A General view of Analysis (G Corti) (? Patterns of group and user analysis) MC generator Raw Data DST (reconstructed particles, primary vertex) Reconstruction Data Acquisition Detector Simulation (Group) Analysis MC “truth”Data “Reconstructed” Physics channels Physicist Analysis

26 Nov 1999 F Harris LHCb computing workshop6 Status of simulated event production (since june) E van Herwijnen

26 Nov 1999 F Harris LHCb computing workshop7 Tasks and Deliverables (2) zResource distribution èProduce description of distribution of LHCb institutes, regional centres and resources (equipment and people), and the connectivity è Resource Map with network connectivity. è List of people and equipment… zSpecial requirements for remote working è (OS platfoms,s/w distribution,videoconferencing..) èURD on ‘Remote working…’ zTechnology Tracking è (Follow PASTA. Data Management s/w, GAUDI data management….) èTechnology trend figures èCapabilities of data management s/w

26 Nov 1999 F Harris LHCb computing workshop8 Mock-up of an Offline Computing Facility for an LHC Experiment at CERN (Les Robertson July 99 with ‘old’ experiment estimates) zPurpose yinvestigate the feasibility of building LHC computing facilities using current cluster architectures, conservative assumptions about technology evolution xscale & performance xtechnology xpower xfootprint xcost xreliability xmanageability

26 Nov 1999 F Harris LHCb computing workshop9

250 Gbps 0.8 Gbps 8 Gbps ………… 1400 boxes 160 clusters 40 sub-farms 12 Gbps* 480 Gbps* 3 Gbps* 1.5 Gbps 100 drives 12 Gbps 5400 disks 340 arrays ……... LAN-SAN routers LAN-WAN routers CERN CMS Offline Farm at CERN circa 2006 lmr for Monarc study- april 1999 tapes 0.8 Gbps (daq) 0.8 Gbps 5 Gbps disks processor s storage network farm network * assumes all disk & tape traffic on storage network double these numbers if all disk & tape traffic through LAN-SAN router

26 Nov 1999 F Harris LHCb computing workshop11 Tasks and Deliverables(3) zCandidate Computer Models evaluation èMap data and tasks to facilities (try different scenarios) èDevelop spreadsheet model with key parameters-get ‘average answers’ èDevelop simulation model with distributions èEvaluate different models (performance,cost,risk…..) èEstablish a BASELINE MODEL è>> BASELINE COMPUTING MODEL together with cost, performance,risk analysis

26 Nov 1999 F Harris LHCb computing workshop12 The Structure of the Simulation Program (I Legrand) z User Directory Config Files Initializing Data Define Activities (jobs) GUI Monarc Package Network Package Data Model Package Auxiliary tools Graphics SIMULATION ENGINE Parameters Prices.... Processing Package Statistics Regional Center, Farm, AMS, CPU Node, Disk, Tape Job, Active Jobs, Physics Activities, Init Functions, LAN, WAN, Messages Data Container, Database Database Index Dynamically Loadable Modules

26 Nov 1999 F Harris LHCb computing workshop13 Proposed composition and organisation of working group zContacts from each country zContacts from other LHCb projects (can/will have multi-function people..) yDAQ yReconstruction yAnalysis yMONARC yIT (PASTA +?) zProject Plan (constraint - timescales to match requests from the review..) zMonthly meetings? (with videoconferencing) y1st meeting week after LHCb week (first try at planning execution of tasks) zDocumentation yall on WWW (need a WEBMASTER)