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Oracle Tech Day November 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland
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Page 1: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

Building the world’s largest Scientific Grid

Jamie ShiersDatabase Group, CERN, Geneva, Switzerland

Page 2: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

22Jamie Shiers November 2004Scientific & Enterprise Grids

Agenda

• The Need for a World-Wide Grid

• An Overview of the World’s Largest Scientific Grid

• The role of the Database Group in the above

• The role of the CERN openlab for DataGrid Applications

• The role of Enterprise Grids

• Summary and Conclusions

Page 3: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

The Requirements

The Large Hadron Collider at CERN(LHC)

Page 4: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

44Jamie Shiers November 2004Scientific & Enterprise Grids

The European Organisation for Nuclear Research

The European Laboratory for Particle Physics• Fundamental research in particle physics• Designs, builds & operates large

accelerators• Financed by 20 European countries

– member states + others (Russia, US, Canada, India, ….)

1BSF budget - operation + new accelerators 2000 staff + 6000 users (researchers) from all over

the world

New accelerator, Large Hadron Collidor (LHC)

Page 5: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

55Jamie Shiers November 2004Scientific & Enterprise Grids

airp

ort

Computer Centre Geneva

27km

Page 6: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

66Jamie Shiers November 2004Scientific & Enterprise Grids

Page 7: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

77Jamie Shiers November 2004Scientific & Enterprise Grids

The LHC machine

• Two counter-circulating proton beams

• Collision Energy 7 + 7 TeV

• 27 Km of magnets with a field of 8.4 Tesla

• Super-fluid Helium cooled to 1.9°K

• The world’s largest superconducting structure!

Page 8: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

88Jamie Shiers November 2004Scientific & Enterprise Grids

The Atlas Detector

• The ATLAS collaboration is – ~2000 physicists from ..– ~ 150 universities and labs – from ~ 35 countries– distributed resources– remote development

• The ATLAS detector is – 26m long, – stands 20m high, – weighs 7000 tons – has 200 million read-out

channels

• One of 4 LHC experiments– ALICE, ATLAS, CMS, LHCb

Page 9: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

99Jamie Shiers November 2004Scientific & Enterprise Grids

All charged tracks with pt > 2 GeV

Reconstructed tracks with pt > 25 GeV

(+30 minimum bias events)

Selectivity: 1 in 1013

- 1 person in a thousand world populations- A needle in 20 million haystacks

LHC: Higgs Decay into 4 muons

Page 10: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

1313Jamie Shiers November 2004Scientific & Enterprise Grids

LHC data

• 40 million collisions per second

• After filtering, 100-200 collisions of interest per second

• 1-10 Megabytes of data digitised for each collision = recording rate of 0.1-1 Gigabytes/sec

• 1010 collisions recorded each year = ~15 Petabytes/year of data

CMS LHCb ATLAS ALICE

1 Megabyte (1MB)A digital photo

1 Gigabyte (1GB) = 1000MBA DVD movie

1 Terabyte (1TB)= 1000GBWorld annual book production

1 Petabyte (1PB)= 1000TBAnnual production of one LHC experiment

1 Exabyte (1EB)= 1000 PBWorld annual information production

Page 11: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

1414Jamie Shiers November 2004Scientific & Enterprise Grids

Agenda

• The Need for a World-Wide Grid

• An Overview of the World’s Largest Scientific Grid

• The role of the Database Group in the above

• The role of the CERN openlab for DataGrid Applications

• The role of Enterprise Grids

• Summary and Conclusions

Page 12: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

The Solution

The Large Hadron Collider Grid(LCG)

Page 13: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

1616Jamie Shiers November 2004Scientific & Enterprise Grids

LCG Project Goals

• To prepare, deploy and operate the computing environment for the experiments to analyse the data from the LHC detectors

• Applications development environment, common tools and frameworks

• Build and operate the LHC computing service

• The Grid is just a tool towards achieving this goal

Page 14: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

1717Jamie Shiers November 2004Scientific & Enterprise Grids

LCG-2/EGEE-0 Status24-09-2004

Total:78 Sites~9000 CPUs6.5 PByte

Total:78 Sites~9000 CPUs6.5 PByte

Cyprus

Page 15: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

1818Jamie Shiers November 2004Scientific & Enterprise Grids

CollaboratingComputer Centres

Building a GridThe virtual LHC Computing CentreGrid

ATLAS Virtual Organisation

CMS Virtual Organisation

Page 16: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2121Jamie Shiers November 2004Scientific & Enterprise Grids

RAL

IN2P3

BNL

FZK

CNAF

PIC ICEPP

FNAL

Tier-1small

centres

Tier-2

desktopsportables

USCNIKHEFKrakow

CIEMATRome

Taipei

TRIUMF

CSCS

Legnaro

UB

IFCA

IC

MSU

Prague

Budapest

Cambridge

IFIC

LHC Computing Model• Tier-0 – CERN

• Filter raw data• Reconstruction summary data (ESD)• Record raw data and ESD• Distribute raw and ESD to Tier-1

• Tier-1 – • Data-heavy analysis• Re-processing raw ESD• National, regional support

• Tier-2 –• End-user analysis – batch and interactive

Page 17: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2222Jamie Shiers November 2004Scientific & Enterprise Grids

RAL

IN2P3

BNL

FZK

CNAF

USC

PIC ICEPP

FNAL

NIKHEFKrakow

Taipei

CIEMAT

TRIUMF

Rome

CSCS

Legnaro

UB

IFCA

IC

MSU

Prague

Budapest

Cambridge

Data distribution~70 Gbits/sec

Processing M SI2000**

Disk PetaBytes

Mass Storage

PetaBytes

CERN 20 5 20

Major data handling centres

(Tier 1)45 20 18

Other large centres (Tier 2)

40 12 5

Totals 105 37 43

** Current fast processor ~1K SI2000

Current estimates of Computing Resources needed at Major LHC Centres

First full year of data - 2008

ProcessingM SI2000**

IC

Page 18: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2323Jamie Shiers November 2004Scientific & Enterprise Grids

2004 Data Challenges

• Large-scale tests of the experiments’ computing models, processing chains, grid technology readiness, operating infrastructure

• The big challenge for this year – - data- file catalogue, - replica management,- database access, - integrating mass storagePlanning for a second operations

& support centre in Taipei

Grid Operations Centreat RAL

User Support Centre at FZK

Page 19: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

Experiences during the data challenges

Page 20: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2525Jamie Shiers November 2004Scientific & Enterprise Grids

Data Challenges – ALICE

• Phase I120k Pb+Pb events produced in 56k jobs1.3 million files (26TByte) in Castor@CERNTotal CPU: 285 MSI-2k hours (2.8 GHz PC working 35 years)~25% produced on LCG-2

Phase II (underway)1 million jobs, 10 TB produced, 200TB transferred ,500 MSI2k hours CPU~15% on LCG-2

Page 21: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2626Jamie Shiers November 2004Scientific & Enterprise Grids

Data Challenges – ATLAS ATLAS DC2 - CPU usage

41%

30%

29%

LCG

NorduGrid

Grid3

• Phase I7.7 Million events fully simulated (Geant 4) in 95.000 jobs22 TByteTotal CPU: 972 MSI-2k hours >40% produced on LCG-2 (used LCG-2, GRID3, NorduGrid)

ATLAS DC2 - LCG - September 71%

2%

0%

1%

2%

14%

3%

1%

3%

9%

8%

3%2%5%1%4%

1%

1%

3%

0%

1%

1%

4%1%

0%

12%

0%

1%

1%

2%

10%

1% 4%

at.uibk

ca.triumf

ca.ualberta

ca.umontreal

ca.utoronto

ch.cern

cz.golias

cz.skurut

de.fzk

es.ifae

es.ific

es.uam

fr.in2p3

it.infn.cnaf

it.infn.lnl

it.infn.mi

it.infn.na

it.infn.na

it.infn.roma

it.infn.to

it.infn.lnf

jp.icepp

nl.nikhef

pl.zeus

ru.msu

tw.sinica

uk.bham

uk.ic

uk.lancs

uk.man

uk.rl

Page 22: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2727Jamie Shiers November 2004Scientific & Enterprise Grids

Data Challenges – CMS

• ~30 M events produced• 25Hz reached

•(only once for a full day)• RLS, Castor, control systems, T1 storage, …

•Not a CPU challenge, but a full chain demonstration•Pre-challenge production in 2003/04

•70 M Monte Carlo events (30M with Geant-4) produced•Classic and grid (CMS/LCG-0, LCG-1, Grid3) productions

Page 23: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2828Jamie Shiers November 2004Scientific & Enterprise Grids

DIRAC alone

LCG inaction

1.8 106/day

LCG paused

3-5 106/day

LCG restarted

Data Challenges – LHCb

• Phase I186 M events 61 TByteTotal CPU: 424 CPU years (43 LCG-2 and 20 DIRAC sites)Up to 5600 concurrent running jobs in LCG-2

This is 5-6 times what was possible at CERN alone

Page 24: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

2929Jamie Shiers November 2004Scientific & Enterprise Grids

Data challenges – Summary

• First time such a set of large scale grid productions has been done?

– Significant efforts invested on all sides – very fruitful collaborations

– Middleware is actually quite stable now

– But – single largest issue is lack of stable operations

• Close to 500TB (half a PB…) of Data Stored

Page 25: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3030Jamie Shiers November 2004Scientific & Enterprise Grids

Preparing for 7,000 boxes in 2008

Page 26: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3131Jamie Shiers November 2004Scientific & Enterprise Grids

LCG Summary

• The LHC Computing Grid is real and is running production

• From a ‘single world-wide Grid’ to a ‘federation of Grids’

• See also Economist, October 7th 2004

Page 27: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3232Jamie Shiers November 2004Scientific & Enterprise Grids

Agenda

• The Need for a World-Wide Grid

• An Overview of the World’s Largest Scientific Grid

• The role of the Database Group in the above

• The role of the CERN openlab for DataGrid Applications

• The role of Enterprise Grids

• Summary and Conclusions

Page 28: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

The Role of the Database Group

Page 29: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3434Jamie Shiers November 2004Scientific & Enterprise Grids

CERN Database Group

• Provides support for Oracle based solutions across whole spectrum of activities of the laboratory:

– Internal e-business applications• Uses, inter alia, Oracle HR

– Technical infrastructure for the laboratory• Accelerator + Detector design, construction and operation

– Physics related services• Will be used in real-time mode for detector monitoring and

calibration• Also for storing some fraction of the scientific data

• CERN has been an Oracle customer since > 20 years!– http://cern.ch/db/

Page 30: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3535Jamie Shiers November 2004Scientific & Enterprise Grids

DB Group – Physics Activities

• Develop and maintain Physics-related Applications– POOL Persistency Framework for storing Physics Data– Conditions DB for conditions of the massive detectors themselves

• These activities part of the LCG Applications Area…

• General Database and Application Server services– Currently at the level of 10-20TB– Essentially all based on Intel / Linux

• Core Grid Services– Includes the LCG File Catalog– Used to schedule jobs (where the data is) and…– For running jobs to access the data

Page 31: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3636Jamie Shiers November 2004Scientific & Enterprise Grids

Physics Activities - Futures

• Re-engineering all DB services for Physics on

Oracle 10g RACOracle 10g RAC

• Goals are:– Isolation – 10g ‘services’ and / or physical separation– Scalability - in both database processing power and storage – Reliability – automatic failover in case of problems– Manageability – significantly easier to administer than now

• Will revisit this under ‘Enterprise Grids’ later…

Page 32: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3737Jamie Shiers November 2004Scientific & Enterprise Grids

CERN & Oracle

• Share a common vision regarding the future of high performance computing– Wide spread use of commodity dual processor PCs running Linux;– Focus on Grid computing

• CERN has managed to influence Oracle product

Oracle 10g features:

– Support for native IEEE floats & doubles;

– Support for “Ultra large” Databases (ULDB);

– Cross-platform transportable tablespaces.

Page 33: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3838Jamie Shiers November 2004Scientific & Enterprise Grids

Agenda

• The Need for a World-Wide Grid

• An Overview of the World’s Largest Scientific Grid

• The role of the Database Group in the above

• The role of the CERN openlab for DataGrid Applications

• The role of Enterprise Grids

• Summary and Conclusions

Page 34: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

3939Jamie Shiers November 2004Scientific & Enterprise Grids

Page 35: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4040Jamie Shiers November 2004Scientific & Enterprise Grids

CERN openlab

• The CERN openlab for DataGrid applications is a framework for evaluating and integrating cutting-edge technologies or services in partnership with industry, focusing on potential solutions for the LCG

• The openlab invites members of the industry to join and contribute systems, resources or services, and carry out with CERN large-scale highly-performing evaluations of their solutions in an advanced integrated environment

• CERN – Oracle focus:– Areas that will lead to tangible benefits in the short-medium term– Also look at longer term, strategic issues Not limited to Physics-specific! Solutions preferably of general

interest!

Page 36: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4141Jamie Shiers November 2004Scientific & Enterprise Grids

openlab - achievements

• DataGuard– Typically viewed as ‘disaster protection’

• (which does happen)

– Also suitable for handling scheduled interventions• Primary cause of interventions in our Grid are O/S security patches• Cannot afford for critical Grid component to be down! (Impacts whole Grid!)

• Streams– Often viewed as ‘some sort of replication technique’ (true)– Has great potential in handling upgrades in a quasi-transparent manner– openlab fellow has demonstrated transparent upgrades:

• From one version of Oracle to another (e.g. 9i to 10g)• From one platform to another (e.g. from Solaris to Intel)

We have sufficient confidence in this technique that we will be using it in production for critical services, e.g. network DB, together with RAC

Page 37: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4343Jamie Shiers November 2004Scientific & Enterprise Grids

simulation

reconstruction

analysis

interactivephysicsanalysis

batchphysicsanalysis

batchphysicsanalysis

detector

event summary data

rawdata

eventreprocessing

eventreprocessing

eventsimulation

eventsimulation

analysis objects(extracted by physics topic)

Physics Analysis

event filter(selection &

reconstruction)

event filter(selection &

reconstruction)

processeddata

les.

rob

ert

son

@ce

rn.c

h

Page 38: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4444Jamie Shiers November 2004Scientific & Enterprise Grids

RAW

ESD

AOD

TAG

randomseq.

1PB/yr (1PB/s prior to reduction!)

100TB/yr

10TB/yr

1TB/yr

Data

Users

Tier0

Tier1

Page 39: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4545Jamie Shiers November 2004Scientific & Enterprise Grids

openlab – future focus

• Ultra-large scientific databases for end-user analysis– An area that is not well understood in current LCG– Exploitation of native floats; low selectivity server-side query– Joint work with other openlab partners!

• World-wide monitoring / deployment– Extensive use of Enterprise Grid Control to handle deployment of core

DB and iAS services– Monitoring, Capacity Planning, Patch Deployment, Backup / Recovery

etc.

• Further development of quasi non-stop services using Oracle Streams, 10g DataGuard + 10g RAC etc

All with focus on early production deployment of successes!

Page 40: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4646Jamie Shiers November 2004Scientific & Enterprise Grids

Page 41: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4747Jamie Shiers November 2004Scientific & Enterprise Grids

Agenda

• The Need for a World-Wide Grid

• An Overview of the World’s Largest Scientific Grid

• The role of the Database Group in the above

• The role of the CERN openlab for DataGrid Applications

• The role of Enterprise Grids

• Summary and Conclusions

Page 42: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

Enterprise Grids

The Role of Enterprise Grids in

Scientific Grids

Page 43: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

4949Jamie Shiers November 2004Scientific & Enterprise Grids

Grid - Component Services

• A Grid such as the LCG is built upon a large number of component services and applications

• Traditional wisdom: – Hand tailor each service according to its specific needs– Hard limits in terms of scalability and capacity– Maintenance nightmare!

• Alternate approach: – Build services in a standard way out of common building blocks– Layer upon an Enterprise Grid– Scalable; Configurable; Manageable.

Page 44: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

5050Jamie Shiers November 2004Scientific & Enterprise Grids

CERN DB Physics Services

• Currently being re-engineered on an Enterprise Grid

– 24 PCs (now) – expand to 36 / 48 end 2005• dual processor, 4GB memory, mirrored system disk, RHEL 3.0

– Redundant (dual) 64-port SAN infrastructure

– Some 50TB of mirrored SAN storage

• Based on Oracle 10g RAC and 10g Services

– Hardware on order – installation expected before Christmas 2004– Watch this space!

Page 45: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

Summary and Conclusions

Page 46: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

5252Jamie Shiers November 2004Scientific & Enterprise Grids

What are Grids all about?

• Grids are about sharing and pooling of resources

• We all know that when we can and do work together we achieve much more than if we work alone– CERN is a classic example of this at a world-wide scale!

Two other examples (from CHEP ’04 in Interlaken, CH)

1. Resilience• Security of valuable data• Continuity in case of major disruption

2. Expedience• Access to additional resources• Engagement of distributed communities

Page 47: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

5353Jamie Shiers November 2004Scientific & Enterprise Grids

The Grid – Disruptive Technology?

• From OracleWorld San Francisco press panel Sep 2003:

[ Work on LHC Computing started around 1992 ]

• “What would happen if something came along that would change everything? Like the Web. We would simply have to take it into account”

• “We believe that thing has come along, and that thing is the grid.”

• “We are actively involved in making it happen, and it is the underlying cornerstone of our computing model”

Page 48: Oracle Tech DayNovember 2004 Building the world’s largest Scientific Grid Jamie Shiers Database Group, CERN, Geneva, Switzerland.

Oracle Tech Day November 2004

The Grid

is unstoppable...


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