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A Summary of CHEP 2007. Victoria, BC, Canada, 2-7 Sept. 2007. Dmitry Emeliyanov, RAL PPD. CHEP’07 : The conference. Total: 474. Expected Audience: attract 500 people 90% from outside of Canada 25% from US. CHEP’07: Some statistics. 429 abstracts submitted with 1208 authors
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A Summary of CHEP 2007 Victoria, BC, Canada, 2-7 Sept. 2007 Dmitry Emeliyanov, RAL PPD
CHEP’07 : The conference Total: 474 • Expected Audience: • attract 500 people • 90% from outside of Canada • 25% from US
CHEP’07: Some statistics • 429 abstracts submitted with 1208 authors • 29 plenary talks and 7 parallel tracks:
Selected topics • Status of the LHC and experiments • Multi-core CPUs and HEP software: news from Intel and view from CERN • Online computing: Trigger and DAQ activities in LHC experiments and beyond • All presentations are available in Indico: http://indico.cern.ch/conferenceTimeTable.py?confId=3580 • paperswill be published in Journal of Physics Conference Series
General LHC schedule T. Virdee (CERN/Imperial) • Engineering run originally foreseen at end 2007 now precluded by delays in installation and equipment commissioning • 450 GeV operation now part of normal setting up procedure for beam commissioning to high-energy • General schedule has been revised, accounting for inner triplet repairs and their impact on sector commissioning • All technical systems commissioned to 7 TeV operation, and machine closed April 2008 • Beam commissioning starts May 2008 • First collisions at 14 TeV c.m. July 2008 • Luminosity evolution will be dominated by our confidence in the machine protection system and by the ability of the detectors to absorb the rates. • No provision in success-oriented schedule for major mishaps, e.g. additional warm-up/cooldown of sector
LHC experiments status T. Virdee (CERN/Imperial) • Construction essentially completed • Installation is very advanced - beam pipes closed end March 2008 • Test beam and commissioning work already carried out gives confidence that detectors will behave as expected • Commissioning using cosmics with more and more complete setups (complexity and functionality) • using final readout, trigger and DAQ, software and computing systems • Computing, Software & Analysis 24/7 Challenges, Dress Rehearsals @50% of 2008 expectation by end of 2007. • Preparations for the rapid extraction of physics being made • By spring 2008 experiments will be in 2008 configurations, fields ON, taking cosmics
News from Intel Addressing Future HPC Demand with Multi-core Processors September 5, 2007 Stephen S. Pawlowski Intel Senior Fellow GM, Architecture and Planning CTO, Digital Enterprise Group
Accelerating Multi- and Many-core Power delivery and management High bandwidth memory Reconfigurable cache Scalable fabric Big Core Core Core Core Core Core Core Core Big Core Core Core • Big cores for Single Thread Performance • Small cores for Multi-Thread Performance Fixed-function units Performance Through Parallelism
Heat-sink DRAM CPU Si Chip Si Chip Package Package Addressing Memory Bandwidth 3D Memory Stacking Memory on Package Last Level Cache Fast DRAM *Future Vision, does not represent real Intel product Bringing Memory Closer to the Cores
How good is the match between LHC software and current/future processors? Sverre Jarp CERN openlab CTO CHEP 2007 5 September 2007 5 September 2007 CHEP Plenary - SJ 10
Implications of Moore’s law • Initially the processor was simple • Modest frequency; Single instruction issue; In order; Tiny caches; No hardware multithreading or multi-core; No major problems with cooling • Since then: • Frequency scaling (from 150 MHz to 3 GHz) • Multiple execution ports, wide execution (SSE) • Out-of-order execution, larger caches • Multithreading, Multi-core • Heat All of this has been absorbed without any change to our software model: Single-threaded processes farmed out per processor core.
HEP Software Profile • Our memory usage: • Today, we need 2 – 4 GB per single-threaded process. • In other words, a dual-socket server needs at least: • Single core: 4 - 8 GB, Quad core: 16 - 32 GB • Future 16-way CPU: 64 – 128 GB, 64-way CPU: 256 – 512 GB • “We have floating point work wrapped in ‘if/else’ logic” • Overall estimate: 50% is floating point • Our LHC programs typically issue (on average) only 1 instruction per cycle – This is very low! • Core 2 architecture can handle 4 instructions • Each SSE instruction can operate on 128 bits (2 doubles) • “our LHC programs typically utilizes only 1 instruction per CPU clock cycle (= 1/8 of maximum)” “We are not getting out of first gear”
Core 0 Core 3 Core 1 Core 2 Eventspecificdata Event-specificdata Event-specificdata Event-specificdata Globaldata Physicsprocesses Magneticfield Reentrantcode Recommendations • Industry will bombard us with new designs based on multi-billion transistor budgets • Hundreds of cores • Multiple threads per core • Unbelievable floating-point performance • Clearly, the emphasis now is to get LHC started and there is plenty of compute power across the Grid. • If we want to extract (much) more compute-power out of new chip generations • Try to increase the Instruction Level Parallelism • Investigate “intelligent” multithreading • Reduce our overall memory footprint
Online Computing: CPU farms for high-level triggering; Farm configuration and run control; Describing and managing configuration data and conditions databases; Online software frameworks and tools; online calibration procedures • 48 abstracts total: 27 oral presentations / 21 posters • By experiments: • 38 LHC / 10 non-LHC experiment or generic • ALICE: 4 • ATLAS: 15 • CMS: 14 • LHCb: 5
Data Acquisition at the LHC experiments Plenary talk by Sylvain CHAPELAND (CERN )
LHC Experiments: Trigger and DAQ Status • “Alea iacta est” • All fundamental choices are made • All use commercial components wherever possible • All based on powerful LAN technology and PC server farms • Installation is progressing rapidly • Status reports: • “Integration of the Trigger and Data Acquisition Systems in ATLAS” • “Commissioning of the ALICE Data Acquisition System” • Commissioning and cosmics running • Commissioning of larger and larger slices has started in all 4 experiments • Large scale and Cosmic (ATLAS) tests look already very promising • Extremely valuable feedback • require customized settings / algorithms
Combined Cosmic run in June 2007 In June we had a 14 day combined cosmic run with no magnetic field. Included following systems: Muons – RPC (~1/32) , MDT (~1/16), TGC (~1/36) Calorimeters – EM (LAr )(~50%) & Hadronic (Tile) (~75%) Tracking – Transition Radiation Tracker (TRT) (~6/32 of the barrel of the final system) Only systems missing are the Silicon strips and pixels and the muon system CSCs From “The ATLAS Trigger Commissioning with Cosmic rays” 17
Trigger steering • Sophisticated frameworks for high level trigger steering have been developed • Lightweight (caching of calculations (ATLAS)) • Work both offline and online • Use a data-base for configurations (CMS) • Ready to be given to non-expert physicists! • “The ATLAS High Level Trigger Steering” • “High Level Trigger Configuration and Handling of Trigger Tables in the CMS Filter Farm”
Data Quality Monitoring • Essential for commissioning and running • Works also with “offline” data • Standalone viewers vs plug-ins (e.g. web CMS) • Databases are used to store histograms or to describe them (LHCb) • Reports from all four experiments: • “The ALICE-LHC Online Data Quality Monitoring Framework” • “A software framework for Data Quality Monitoring in ATLAS” • “CMS Online Web Based Monitoring” • “Online Data Monitoring in the LHCb experiment”
Slow and Run Controls • Slow and run-control face huge numbers of elements ~ O(107) • Final run-control is beginning to be used on wide-scale, scalability has been tested. Configuration stored in RDBMS (ALICE, CMS, LHCb) or as objects (ATLAS) • All run-controls support partitioning and use finite state machines • “The ATLAS DAQ System Online Configurations Database Service Challenge” • “The Run Control and Monitoring System of the CMS Experiment” • Detector Control is maybe “slow” but certainly big: “The CMS Tracker Control System”, O(50000) HV channels + O(100000) environment sensors controlled by 5 PCs
TDAQ Activities Outside the LHC • Reports from mature systems • “The DZERO Run 2 L3/DAQ System Performance” • “The PHENIX Experiment in the RHIC Run 7” • “The BaBar Online Detector Control System Upgrade” • And new frameworks • “Multi-Agent Framework for Experiment Control Systems (AFECS)” • Successful upgrades (to overcome legacy hardware), hardware extensions, high availability, running with very small crews
The D0 Run II L3/DAQ System Performance • Mainly run by 3 (part-time) people • Heterogeneous trigger farm scaled up from 90 to ~ 330 nodes • Has lived reliably through numerous detector and hardware upgrades
To summarize ... • The LHC experiments are looking forward to seeing the first data • All core DAQ components have been tested • Good fraction of equipment is installed (except for the filter farms and part of the DAQ network) • Integration and Commissioning are well underway • A lot of activity in trigger control and steering • Handing over to the physicists • Monitoring frameworks evolving quickly Many interesting Online stories will be told at the next CHEP
CHEP 2009 • Will be held in Prague, Czech Republic on 21-27 March 2009