LHC Computing Grid Project LCG

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• LHC Computing Grid Project LCG
• Les Robertson LCG Project Leader
• CERN European Organisation for Nuclear Research
• Geneva, Switzerland
• March 2005

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1 Megabyte (1MB) A digital photo 1 Gigabyte
(1GB) 1000MB A DVD movie 1 Terabyte (1TB)
1000GB World annual book production 1 Petabyte
(1PB) 1000TB 10 of the annual production by
LHC experiments 1 Exabyte (1EB) 1000 PB World
annual information production
LHC data (simplified)

• Per experiment
• 40 million collisions per second
• After filtering, 100 collisions of interest per
  second
• A Megabyte of digitised information for each
  collision recording rate of 100 Terabytes/sec
• 1 billion collisions recorded 1 Petabyte/year

With four experiments, processed data we will
accumulate 15 PetaBytes of new data each year
CMS
LHCb
ATLAS
ALICE
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The LHC Data Challenge
Starting from this event
Selectivity 1 in 1013 Like looking for 1
person in a thousand world populations! Or for a
needle in 20 million haystacks!
You are looking for this signature
We will need 100,000 of todays fastest PCs
to extract the physics from all of this data
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Data Handling and Computation for Physics Analysis
reconstruction
event filter (selection reconstruction)
detector
analysis
processed data
event summary data
raw data
batch physics analysis
event reprocessing
analysis objects (extracted by physics topic)
event simulation
interactive physics analysis
les.robertson_at_cern.ch
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LCG-2
120 Grid sites 10,000 CPUs 10 PetaBytes
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LCG Service Hierarchy

• Tier-2 100 centres in 40 countries
• Simulation
• End-user analysis batch and interactive

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Tape
Preliminary planning data
Requirements from December 2004 computing model
papers Reviewed by LHCC Jan 05
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LHC Computing Grid Project - a Collaboration
Building and operating the LHC Grid
a global collaboration between

• The physicists and computing specialists from the
  LHC experiments
• The projects in Europe and the US that have been
  developing Grid middleware
• The regional and national computing centres that
  provide resources for LHC
• The research networks

Researchers
Computer Scientists Software Engineers
Service Providers
Virtual Data Toolkit
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Summary

• LHC computing
• Data intensive - Geographically distributed
• Independent regional centres
• LHC Grid
• Reliable environment for data intensive batch
  work
• An early example of a working data-intensive grid
• Co-existing with multiple grids, other sciences
• Current status
• Large global grid established and being used
  for real work by LHC experiments
• Middleware basic functionality, reliability
  performance issues
• Learning how to operate a facility with 150
  centres
• Ambitious schedule to achieve required service
  level by March 2007
• Long-term expectation
• Science grids operated as national/international
  infrastructure