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The Grid at CERNVisit to the
CERN Computer Center
Key messages for the General Public
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Computing for the LHC 1 billion proton-proton collision events
per
second in the detectors (40 million bunchcrossings per
second)
After filtering, 100 collisions of interest per
second recorded permanently
A few Megabytes of data digitised for eachcollision in each
experiment = recording rate of 1 Gigabytes/sec
10 10 collisions recorded each year = 10Petabytes/year of
data
Including raw data, processed data andsimulated data, the LHC
will produce each year about 15 Petabytes (15 million Gigabytes) of
data
1 Megabyte (1MB) A digital photo
1 Gigabyte (1GB) = 1000MB 5GB = A DVD movie
1 Terabyte (1TB) = 1000GB World annual book production
1 Petabyte (1PB)
= 1000TB Annual production of one LHC experiment
1 Exabyte (1EB) = 1000 PB 3EB = World annual information
production
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A problem: LHC data and its analysis
LHC data correspond to about 20 million CDs each year. Where
willthe experiment store all of these data?
LHC data analysis will require a total computing power
equivalent to
~ 100,000 of todays standard PC processors. Where will
theexperiments find such a computing power?
CERN CC has today around 2000 dual processor PCs and canstore 5
Petabytes of data on disk and tapes. Nowhere near enough!
Problem: CERN alone can provide only afraction of the necessary
resources
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A solution: the Grid
A solution is to connect computing centers through theGrid ,
uniting the computing resources of particlephysicists in the world!
Europe: 267 institutes, 4603 users
Elsewhere: 208 institutes, 1632 users
What is the Grid? Analogy Web Grid:
The World Wide Web provides seamlessaccess to informationthat is
stored in manymillions of differentgeographical locations
The Grid providesseamless access tocomputing power anddata
storage capacitydistributed over the globe
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Grid Challenges at CERN Share data between >7000 scientists
around the globe Link major computer centres , not just PCs Ensure
that all the data is accessible anywhere,
anytime Ensure rapid yet reliable growth of the Grid over
more
than a decade Integrate the many policies and rules that
govern
usage of different resources in different countries
Ensure the data are secure and cannot bemisappropriated (there
are Nobel prizes at stake!)
Be up and running by 2007
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Grid projects at CERN (I) LHC Computing Grid project (LCG)
A Grid for physics, dedicated to the LHC scientists toaccess and
analyse the LHC data
Currently operates the worlds largest scientific Grid,with over
130 sites in 31 countries contributingresources, including more
than 10,000 CPUs andseveral Petabytes of storage.
Enabling Grid for E-sciencE A EU funded project led by CERN
involving experts
from 27 countries in 5 continents Building a Grid infrastructure
for ALL sciences, giving
researchers in academia and industry access to major computing
resources 24 hours-a-day
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The CERN Computer Centre Visit
VERY IMPORTANT FOR YOUR SECURITY
PLEASE DO NOT TOUCH ANY EQUIPMENT ORCABLES DURING THE
TOUR!!!
Upper floor: CERN openlabDataTAGCIXP
Lower floor:StorageTek silosPC farm
