1 A Summary of CHEP 2007 Dmitry Emeliyanov, RAL PPD Victoria, BC, Canada, 2-7 Sept. 2007.
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Transcript of 1 A Summary of CHEP 2007 Dmitry Emeliyanov, RAL PPD Victoria, BC, Canada, 2-7 Sept. 2007.
1
A Summary of CHEP 2007A Summary of CHEP 2007
Dmitry Emeliyanov, RAL Dmitry Emeliyanov, RAL PPDPPD
Victoria, BC, Victoria, BC, Canada, Canada,
2-7 Sept. 2-7 Sept. 20072007
2/24
CHEP’07 : The conferenceCHEP’07 : The conference• Expected
Audience:• attract 500
people• 90% from
outside of Canada
• 25% from US
Total: 474
3/24
CHEP’07: Some statisticsCHEP’07: Some statistics
CHEP Presentations and Posters
0
10
20
30
40
50
60
70
80
90
Onlinecomputing
Softwarecomponents,
tools anddatabases
Computerfacilities,productiongrids and
networking
Collaborativetools
Distributeddata analysis
andinformation
management
Eventprocessing
Gridmiddlewareand tools
PresentationPoster
• 429 abstracts submitted with 1208 authors• 29 plenary talks and 7 parallel tracks:
4/24
Selected topicsSelected 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
• papers will be published in Journal of Physics Conference Series
5/24
General LHC scheduleGeneral LHC scheduleT. 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
6/24
LHC experiments statusLHC experiments status
• 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
T. Virdee (CERN/Imperial)
77
Addressing Future HPC Demand Addressing Future HPC Demand with Multi-core Processorswith Multi-core Processors
Stephen S. PawlowskiStephen S. PawlowskiIntel Senior FellowIntel Senior Fellow
GM, Architecture and PlanningGM, Architecture and PlanningCTO, Digital Enterprise GroupCTO, Digital Enterprise Group
September 5, 2007
News from IntelNews from Intel
88
Accelerating Multi- and Many-Accelerating Multi- and Many-corecore
Performance Through ParallelismPerformance Through Parallelism
Power delivery and management
High bandwidth memory
Reconfigurable cache
Scalable fabric
Fixed-function units
Big Core
Core
Core
Core
Core Core
Core Core
Core CoreBig Core
•Big cores for Single Thread Performance
Big cores for Single Thread Performance
•Small cores for Multi-Thread Performance
Small cores for Multi-Thread Performance
99
Addressing Memory BandwidthAddressing Memory Bandwidth
Bringing Memory Closer to the CoresBringing Memory Closer to the Cores
Package
DRAM
CPU
Heat-sink
Last Level Cache
Fast DRAM
Memory on Package
*Future Vision, does not represent real Intel product
3D Memory Stacking
Package
Si Chip Si Chip
105 September 2007 CHEP Plenary - SJ 10
How good is the match
between LHC software and
current/future processors?
Sverre Jarp
CERN openlab CTO
CHEP 2007
5 September 2007
11
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.
12
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”
13
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
Reentrantcode
Magneticfield
Physicsprocesses
Globaldata
Eventspecific
data
Core 0
Event-specific
data
Core 1
Event-specific
data
Core 2
Event-specific
data
Core 3
14
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
15
Data Acquisition at the LHC experimentsPlenary talk by Sylvain CHAPELAND (CERN )
16
• “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
LHC Experiments: Trigger and DAQ Status
17
Combined Cosmic run in June 2007
17
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”
18
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”
19
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”
20
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
21
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
22
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
23
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
24/24
CHEP 2009CHEP 2009
• Will be held in Prague, Czech Republic on 21-27 March 2009