The LHC Computing Grid A World-Wide Computer Centre

Frédéric Hemmer, CERN, IT Department

1

The LHC Computing Grid – April 2007

The LHC Computing Grid

A World-Wide Computer

Centre

Frédéric Hemmer

Deputy IT Department Head

April 13, 2007

Pour Stéphanie Benz

Journaliste – l’Expansion


2


The accelerator generates 40 million particle collisions (events) every second at the centre of each of the four experiments’ detectors

The LHC Accelerator


3


LHC DATA

This is reduced by online computers that filter out a few hundred “good” events per sec.

Which are recorded on disk and magnetic tapeat 100-1,000 MegaBytes/sec

~15 PetaBytes per year for all four experiments


4


simulation

reconstruction

analysis

interactivephysicsanalysis

batchphysicsanalysis

batchphysicsanalysis

detector

event summary data

rawdata

eventreprocessing

eventreprocessing

eventsimulation

eventsimulation

analysis objects(extracted by physics topic)

Data Handling and Computation for

Physics Analysisevent filter(selection &

reconstruction)

event filter(selection &

reconstruction)

processeddata

les.

rob

ert

son

@ce

rn.c

h

CERN


5


The LHC Data Challenge

• The accelerator will be completed in 2007 and run for 10-15 years

• Experiments will produce about15 Million Gigabytes of data each year (about 20 million CDs!)

• 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


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


7


LCG Service Hierarchy

Tier-0 – the accelerator centre• Data acquisition & initial processing• Long-term data curation Data Distribution to Tier-1 centres

Canada – Triumf (Vancouver)France – IN2P3 (Lyon)Germany –KarlsruheItaly – CNAF (Bologna)Netherlands – NIKHEF/SARA (Amsterdam)Nordic countries – distributed Tier-1

Spain – PIC (Barcelona)Taiwan – Academia SInica (Taipei)UK – CLRC (Oxford)US – FermiLab (Illinois) – Brookhaven (NY)

Tier-1 – “online” to the data acquisition process high availability

• Managed Mass Storage – grid-enabled data service

All re-processing passes• Data-heavy analysis• National, regional support

Tier-2 – ~100 centres in ~40 countries• Simulation• End-user analysis – batch and interactive Services, including Data Archive and Delivery, from Tier-1s


8


CERN18%

All Tier-1s39%

All Tier-2s43%

CERN12%

All Tier-1s55%

All Tier-2s33%

CERN34%

All Tier-1s66%

CPU Disk Tape

Summary of Computing Resource RequirementsAll experiments - 2008From LCG TDR - June 2005

CERN All Tier-1s All Tier-2s TotalCPU (MSPECint2000s) 25 56 61 142Disk (PetaBytes) 7 31 19 57Tape (PetaBytes) 18 35 53

Distribution of Computing Services


9


LHC Computing Grid Project - a Collaboration

• The physicists and computing specialists from the LHC experiments

• The national and regional 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

Building and operating the LHC Grid – a global collaboration between


10


The Grid used by CERN and its partners

• The EGEE and OSG projects are the basis of the Worldwide LHC Computing Grid Project


11



12


The new European Network Backbone

• LCG working group with Tier-1s and national/ regional research network organisations

• New GÉANT 2 – research network backbone

Strong correlation with major European LHC centres

• Swiss PoP at CERN


13


• LCG has been the driving force for the European multi-science Grid EGEE (Enabling Grids for E-sciencE)

• EGEE is now a global effort, and the largest Grid infrastructure worldwide

• Co-funded by the European Commission (~130 M€ over 4 years)

• EGEE already used for >20 applications, including…

Impact of the LHC Computing Gridin Europe

Medical ImagingEducation, TrainingBio-informatics


14


The EGEE Project• Infrastructure operation

• Currently includes >200 sites across 40 countries• Continuous monitoring of grid services & automated site

configuration/managementhttp://gridportal.hep.ph.ic.ac.uk/rtm/

• Middleware• Production quality middleware distributed under business

friendly open source licence

• User Support - Managed process from first contact through to production usage

• Training• Documentation • Expertise in grid-enabling applications• Online helpdesk• Networking events (User Forum, Conferences etc.)

• Interoperability• Expanding interoperability with related infrastructures


15


0

5000

10000

15000

20000

25000

30000

35000

40000

Apr-0

4

Jun-

04

Aug-0

4

Oct-

04

Dec-0

4

Feb-0

5

Apr-0

5

Jun-

05

Aug-0

5

Oct-

05

Dec-0

5

Feb-0

6

Apr-0

6

Jun-

06

Aug-0

6

Oct-

06

Dec-0

6

No

. CP

U

0

50

100

150

200

250

Apr-0

4

Jun-

04

Aug-0

4

Oct-

04

Dec-0

4

Feb-0

5

Apr-0

5

Jun-

05

Aug-0

5

Oct-

05

Dec-0

5

Feb-0

6

Apr-0

6

Jun-

06

Aug-0

6

Oct-

06

Dec-0

6

No

. Sit

es

Status

~17.5 million jobs run (6450 cpu-years) in 2006;

Workloads of the “other VOs” start to be significant – approaching 8-10K jobs per day; and 1000 cpu-months/month

• one year ago this was the overall scale of work for all VOs

~17.5 million jobs run (6450 cpu-years) in 2006;

Workloads of the “other VOs” start to be significant – approaching 8-10K jobs per day; and 1000 cpu-months/month

• one year ago this was the overall scale of work for all VOs


17


Use of the EGEE Infrastructure

>20k jobs running simultaneously


18


Use for massive data transfer

Large LHC experiments now transferring ~ 1PB/month each


19


Site availability – SAM


21


Applications on EGEE• More than 20 applications from 7 domains

• Astrophysics• MAGIC, Planck

• Computational Chemistry• Earth Sciences

• Earth Observation, Solid Earth Physics, Hydrology, Climate • Financial Simulation

• E-GRID• Fusion• Geophysics

• EGEODE• High Energy Physics

• 4 LHC experiments (ALICE, ATLAS, CMS, LHCb)• BaBar, CDF, DØ, ZEUS

• Life Sciences• Bioinformatics (Drug Discovery, GPS@, Xmipp_MLrefine, etc.)• Medical imaging (GATE, CDSS, gPTM3D, SiMRI 3D, etc.)

• Multimedia• Material Sciences • …


22


Example: EGEE Attacks Avian Flu

• EGEE used to analyse 300,000 possible potential drug compounds against bird flu virus, H5N1.

• 2000 computers at 60 computer centres in Europe, Russia, Taiwan, Israel ran during four weeks in April - the equivalent of 100 years on a single computer.

• Potential drug compounds now being identified and ranked

Neuraminidase, one of the two major surface proteins of influenza viruses, facilitating the release of virions from infected cells. Image Courtesy Ying-Ta Wu, AcademiaSinica.


23


Example: Geocluster industrial application

• The first industrial application successfully running on EGEE

• Developed by the Compagnie Générale de Géophysique (CGG) in France, doing geophysical simulations for oil, gas, mining and environmental industries.

• EGEE technology helps CGG to federate its computing resources around the globe.


25


Evolution

EGEE EGEE-IIEDG EGEE-III

European e-Infrastructure

Coordination

Testbeds Utility ServiceRoutine Usage


27


The LHC Computing Grid A World-Wide Computer Centre

Documents

Transcript of The LHC Computing Grid A World-Wide Computer Centre