Predrag BUNCIC, Thorsten KOLLEGER & Pierre VANDE VYVRE - PowerPoint PPT Presentation

Predrag BUNCIC, Thorsten KOLLEGER & Pierre VANDE VYVRE ALICE-USA, May 2013, CERN

Requirements and Strategy • Focus of ALICE upgrade on physics probes requiring high statistics: sample 10 nb -1 • Online System Requirements  Sample full 50kHz Pb-Pb interaction rate (current limit at ~500Hz, factor 100 increase)   ~1.1 TByte/s detector readout but the ALICE data processing power capacity will not allow more than a Storage bandwidth of ~20 GByte/s  Many physics probes: classical trigger/event filter approach not efficient • Massive data volume reduction  Data reduction by (partial) online reconstruction and compression • Store only reconstruction results, discard raw data • Demonstrated with TPC clustering since Pb-Pb 2011 • Optimized data structures for lossless compression • Algorithms designed to allow for offline reconstruction passes with improved calibrations •  Implies much tighter coupling between online and offline reconstruction software P. Buncic, T. Kollegger, P. Vande Vyvre 2 ALICE USA - 2013-05

Online-Offline Computing (O 2 ) • 3 projects: DAQ, HLT, Offline  LS1, Run 2 : Prepare (update) and operate 3 independent systems  LS2 upgrade (re-design and implement) “Upgrade of the ALICE Experiment”, Letter Of Intent (LoI), CERN-LHCC-2012-12)  Run 3 : 1 common new online and offline computing system Run 1 LS1 Run 2 LS2 Run 3 LS3 Run 4 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024-26 DAQ Prepare Operate HLT Prepare Operate OFF Prepare Operate LS2 Upgrade Operate Common System Panel TDR • LS2 upgrade  Software panel  Common Technical Design Report (TDR) by September 2014  Common computing farm and software framework in production by 2018 P. Buncic, T. Kollegger, P. Vande Vyvre 3 ALICE USA - 2013-05

Software Panel • Panel (6 people of DAQ, HLT, offline) • Worked on how to go about a common software framework  Started in March and final report in December 2012  The final report is the basis of our future work  Success of the panel also successfully experienced the way we will work in the future • Computing Working Groups (CWGs)  People from DAQ, HLT, offline and detector groups according to needs and availability  Working together on a common topic  Delivering a result (report, procedure, code) adopted by all P. Buncic, T. Kollegger, P. Vande Vyvre 4 ALICE USA - 2013-05

O 2 Computing • 11 Computing Working Groups (CWGs) have started to work • 2 CWGs will start later • More could be added Project O 2 Steering Board Leaders Projects DAQ HLT Offline CWG2 CWG1 CWG3 CWG4 CWG5 CWG6 Computing Procedure & Architecture DataFlow Data Model Platforms Calibration Tools Working Groups CWG9 CWG10 CWG12 CWG7 CWG8 CWG11 Reconstruc. Simulation Sw Lifecycle QA, DQM, Vi Control Hardware CWG13 CWGnn CWGnn CWGnn CWGnn CWGnn Sw ----- ----- ----- ----- ----- Framework Online Institution Computing Institution Boards Board Board P. Buncic, T. Kollegger, P. Vande Vyvre 5 ALICE USA - 2013-05

Computing Working Groups (1) Computing Working Group Main tasks and topics Milestones & Deliverables - Propose the general architecture including the distributed Q4 2013 Online system conceptual design note computing Architecture, - Design the overal framework, define components and 1 Framework & Distrib. Q2 2014 interfaces Sw fw architecture proposal Comput. - Propose survey and evaluation procedures Q2 2013 Procedures and policies draft prop. Tools, guidelines, - Propose common guidelines and policies Q3 2013 Procedures and policies proposal 2 procedures - Select tools to implement procedures, policies and Q3 2013 Common tools proposal development environment - Design and develop mechanisms to exchange & share Q3 2013 Dataflow simulation physics & conditions data Dataflow 3 - Communication, data transport, dataflow control and & ‌ Condition Data Q4 2013 Dataflow design proposal config, Shuttle, OCDB - Computing system simulation Q2 2014 Dataflow demonstrator - Study the functional and performance aspects of the data Q42013 Data model proposal model 4 Data model - Data format and data exchange Q2 2014 Data model demonstrator - Data compression - Study parallel technologies and alternative platforms Q3 2013 Define list of platforms and benchmarks (Atom, ARM, etc) - Define contraints for an effective usage of parallel 5 Computing Platforms Q4 2013 Guidelines use of parallel plaforms hw+sw technologies - Assess the advantages of sw contructions e.g. threads, Q2 2014 Proposal on the use of parallelism processes - Control: Experiment control system Q4 2013 Survey of methods and Control, config. & - Configuration tools for the exp. Control 10 monitoring - Bookeeping and monitoring : Alarm system and eLogBook Q2 2014 Tools selection + demonstrator - Test and recommend commercial hw - Design and develop custom hw Q4 2013 First tests os the key technologies 12 Computing hardware - Purchase, install and administrate the reference and production systems Q2 2014 A few options for each hw item P. Buncic, T. Kollegger, P. Vande Vyvre 6 ALICE USA - 2013-05

Computing Working Groups (2) Computing Working Group Main tasks and topics Milestones & Deliverables - On-line calibration In close contact with PWG-PP 6 Calibration Calibration - Asses the feasibility of automatic calibration procedures - Study the online frame-based reconstruction In close contact with PWG-PP 7 Reconstruction Tracking and Alignment - Asses the feasibility of time frame based reconstruction - Study the physics simulation inc. on time-frames and continuous readout In close contact with PWG-PP 8 Physics simulation Embedding & Mix, Monte-Carlo - Physics simulation packages - Online and offline DQM and QA 9 QA, DQM, visualization In close contact with PWG-PP QA - Data visualization, event display - Implement the complete software lifecycle : development, Q3 2013 Lifecycle draft proposal releases, QC - Implement policies defined by CWG2 on the reference 11 Software Lifecycle Q4 2013 Lifecycle proposal system - Code quality enforcement system Q1 2014 Reference system in production - Design and develop an analysis framework and associated Q4 2013 Design note tools Demonstrate the improvement 13 Software framework - Define an AOD data format Q2 2014 compared - Study the global performances for batch and interactive to the present framework P. Buncic, T. Kollegger, P. Vande Vyvre 7 ALICE USA - 2013-05

Deliverables & Milestones • TDR  Procedure, internal notes  Technology choice or options  Algorithms  Demonstrators, prototypes  TDR section • O 2 deliverables for the future system  Custom component (hw, fw, sw)  Commercial component (hw, fw, sw) P. Buncic, T. Kollegger, P. Vande Vyvre 8 ALICE USA - 2013-05

O 2 Institutes • Institutes  FIAS, Frankfurt, Germany  IIT, Mumbay, India  IPNO, Orsay, France  IRI, Frankfurt, Germany  Rudjer Bošković Institute, Zagreb, Croatia  SUP, Sao Paulo, Brasil  University Of Technology, Warsaw, Poland  Wiegner Institute, Budapest, Hungary  CERN, Geneva, Switzerland • Looking for more people  Need people with computing skills and from detector groups • CWG’s membership is neither closed nor rigid:  New members more than welcome to join  Must be explicit and agreed by the group leader P. Buncic, T. Kollegger, P. Vande Vyvre 9 ALICE USA - 2013-05

O 2 Budget Item Cost [MCHF] DDL Fibres Detector read-out fibres 0.9 EPN Event Processing Nodes 4.1 FLP and C-RORC Detector read-out nodes 0.9 Infrastructure Racks, power, cooling 1.3 Networks Network equipment at Point 2 0.8 Servers Control, configuration, monitoring 0.5 Storage Data storage 0.6 Central DCS 0.2 Total (50 kHz) Total for a 50 kHz read-out rate 9.3 Total (100 kHz) Total for a 100 kHz read-out rate 15.1 Year Fraction [%] • O 2 budget not yet fully covered 2017 32 • Draft spending profile 2017-19 2018 29 2019 39 P. Buncic, T. Kollegger, P. Vande Vyvre 10 ALICE USA - 2013-05

Logistics: Mailing Lists • Mailing lists  https://e-groups.cern.ch/  Lists: alice-o2-xxx • Mailing lists archives  https://groups.cern.ch/group/alice-o2-cwgxx/  Accessible by all ALICE members P. Buncic, T. Kollegger, P. Vande Vyvre 11 ALICE USA - 2013-05

Logistics: Indico and Twiki • CWG2 is defining now in more details the procedures and tools of the O 2 project • Some tools selected in order to start the work • Indico O 2 area: https://indico.cern.ch/categoryDisplay.py?categId=4601 • Wiki O 2 area: https://twiki.cern.ch/twiki/bin/viewauth/ALICE/AliceO2 P. Buncic, T. Kollegger, P. Vande Vyvre 12 ALICE USA - 2013-05

Thanks!

Event Size Event Size (MByte) Detector After Zero After Data Suppressi Compressi on on TPC 20.0 1.0 TRD 1.6 0.2 ITS 0.8 0.2 Others 0.5 0.25 Total 22.9 1.65 • Expected data sizes for minimum bias Pb-Pb collisions at full LHC energy P. Buncic, T. Kollegger, P. Vande Vyvre 14 ALICE USA - 2013-05