The Worldwide LHC Computing Grid
Inauguration Ceremony of the
GRID-CERN Laboratory
Kavala, Greece
Tuesday 9 June 2015
Frédéric Hemmer
CERN IT Department Head
The ATLAS experiment
CERN IT Department
CH-1211 Genève 23
Switzerland
www.cern.ch/it
7000 tons, 150 million sensors
generating data 40 millions times per second
i.e. a petabyte/s
Frédéric Hemmer
2
A collision at LHC
Frédéric Hemmer
3
3
The Data Acquisition
Ian.Bird@cern.ch
4
Frédéric Hemmer
4
Tier 0 at CERN: Acquisition, First pass reconstruction,
Storage & Distribution
2011: 4-6 GB/sec
2011: 400-500 MB/sec
1.25 GB/sec (ions)
9 June 2015
Frédéric Hemmer
5
The LHC Data Challenge
• The accelerator will run for 20
years
• Experiments are producing
about 25 Million Gigabytes of
data each year (about 3 million
DVDs – 850 years of movies!)
• LHC data analysis requires a
computing power equivalent to
~100,000 of today's fastest PC
processors
• Requires many cooperating
computer centres, as CERN can
only provide ~20% of the
capacity
CERN IT Department
CH-1211 Genève 23
Switzerland
www.cern.ch/it
Frédéric Hemmer
6
Solution: the Grid
• Use the Grid to unite computing resources
of particle physics institutes around the
world
The World Wide Web
provides seamless access to
information that is stored in
many millions of different
geographical locations
The Grid is an infrastructure
that provides seamless
access to computing power
and data storage capacity
distributed over the globe
CERN IT Department
CH-1211 Genève 23
Switzerland
www.cern.ch/it
Frédéric Hemmer
7
WLCG – what and why?
•
•
A distributed computing
infrastructure to provide the
production and analysis
environments for the LHC
experiments
Managed and operated by a
worldwide collaboration
between the experiments and
the participating computer
centres
•
The resources are distributed
– for funding and sociological
reasons
•
Our task was to make use of
the resources available to us –
no matter where they are
located
Tier-0 (CERN):
• Data recording
• Initial data reconstruction
• Data distribution
Tier-2 (~140 centres):
• Simulation
• End-user analysis
Tier-1 (12 centres):
• Permanent storage
• Re-processing
• Analysis
•
•
•
•
•
Frédéric Hemmer
~ 160 sites, 35 countries
300000 cores
200 PB of storage
2 Million jobs/day
10 Gbps links
8
Data 2008-2013
Tape Usage Breakdown
CERN Tape Writes
27 PB
23 PB
15 PB
CERN Tape Archive
CERN Tape Verification
Data Loss: ~65 GB over 69 tapes
Duration: ~2.5 years
9 June 2015
Frédéric Hemmer
9
No stop for the Computing !
9 June 2015
Frédéric Hemmer
10
Processing on the Grid
7.E+07
6.E+07
Jobs/Month
5.E+07
4.E+07
lhcb
3.E+07
cms
2M Jobs/day
atlas
2.E+07
alice
1.E+07
Apr-2013
Oct-2012
Apr-2012
Oct-2011
Oct-2010
Apr-2011
Apr-2010
Oct-2009
Apr-2009
Oct-2008
Oct-2007
Apr-2008
Apr-2007
Oct-2006
Apr-2006
Oct-2005
Oct-2004
Apr-2005
0.E+00
1.60E+09
1.4 109 HEPSPEC06/Month
(210 K CPU continuous use)
Close to full capacity
HEPSPEC06 Hours/Month
1.40E+09
1.20E+09
1.00E+09
lhcb
8.00E+08
cms
6.00E+08
atlas
4.00E+08
alice
2.00E+08
Frédéric Hemmer
Oct-2012
Apr-2013
Apr-2012
Oct-2011
Oct-2010
Apr-2011
Apr-2010
Oct-2009
Apr-2009
Oct-2008
Apr-2008
Oct-2007
Apr-2007
Oct-2006
Apr-2006
Oct-2005
Apr-2005
CERN IT Department
CH-1211 Genève 23
Switzerland
www.cern.ch/it
Oct-2004
0.00E+00
11
Broader Impact of the LHC
Computing Grid
• WLCG has been leveraged on both sides of
the Atlantic, to benefit the wider scientific
community
– Europe:
• Enabling Grids for E-sciencE
(EGEE) 2004-2010
• European Grid Infrastructure
(EGI) 2010--
– USA:
• Open Science Grid (OSG)
2006-2012 (+ extension?)
• Many scientific applications 
Frédéric Hemmer
Archeology
Astronomy
Astrophysics
Civil Protection
Comp. Chemistry
Earth Sciences
Finance
Fusion
Geophysics
High Energy
Physics
Life Sciences
Multimedia
Material Sciences
12
…
LHC is restarting …
9 June 2015
Frédéric Hemmer
13
9 June 2015
Frédéric Hemmer
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9 June 2015
Frédéric Hemmer
15
GR-12-TEIKAV Up and Running!
9 June 2015
Frédéric Hemmer
16
CERN School of Computing 2015
9 June 2015
Frédéric Hemmer
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9 June 2015
Frédéric Hemmer
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