nick brook university of bristol the lhc experiments & lattice eb news brief overview of the...

Nick Brook

University of Bristol

The LHC Experiments & Lattice

• EB News

• Brief overview of the expts

LHCb

CMS

ATLAS

Lattice

14th Feb 2002 Nick Brook – Cambridge GridPP

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• New phase for EB – moving from focussing on post “creation” to the need for exploitation and utilisation of GridPP resources– true measure of the success of the project!

• Remit:– To ensure that the GridPP project is ‘experimentally-

driven’– ‘Long term’ planning – assessment of needs and reqts

from GridPP– Dissemination of experiences and information between

UK collaborations– To facilitate close working relationship between expts.– Overall liaison between the expts & GridPP

Experiments BoardExperiments Board


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• Next meeting– Late March, after LCG startup workshop

• Area of discussions:– status of recruitment– status & experience of Grid work– long term plans (changes to original

submissions)– reporting procedures to GridPP

i. testbed experiencesii. management & "booking" of UK Grid resourcesiii. quarterly reporting to TB

Experiments Board(2)Experiments Board(2)


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• Andrew McNab has set up a GridPP virtual organisation for work within UK

• But UK expt. people wishing to use the EDG testbed should register through their collaboration:

– Joel Closier (CERN - LHCb)– Andrea Sciaba (Pisa – CMS)– Alessandro de Salvo (Roma I – ATLAS)

Virtual OrganisationsVirtual Organisations


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Current StatusCurrent Status

RAL has been large contributor to worldwide Monte Carlo production. Globus already used for job submission

PVSS II installed (W2000) at RAL to gain experience with existing distributed control system

LHCb OO reconstruction program (Brunel) reinstalled at RAL for DST production/monitoring. Requires gcc 2.95.2 compiler - awaiting “official” CSF install

Technical problems with current production – need i/p traffic out of RAL (firewall problem) from worker nodes for java book-keeping program

Bristol & Liverpool (MAP) also contribute to MC production. NT production also available from Bristol. MC production from Oxford is imminent


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Current Status(2)Current Status(2)

First tranche, 1 post:• Oxford post filled (Carmine Cioffi), to work on Gaudi (software

framework) persistency services• Initial project: Physical/logical filename services within Gaudi

Second tranche (1 post + 2 ATLAS/LHCb):• post for MC monitoring and control software advertised. Interviews

in March.• Gaudi posts:

• Oxford due to start end of February – (Alexander Soroko)• Cambridge due to start mid-March (suitable candidate found)

Informal discussion with ATLAS UK in the area of installation tools

MC test production has been achieved using EDG middleware release (not in UK though!)


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PlansPlans

RAL remains LHCb’s UK primary testbed site. Interest from Bristol, ScotGrid, Oxford, …

Data Challenges due to take place over summer (June-September) planning is still ongoing (discussion at s/w week beginning of March)

• (~50-100 CPUs for June & September) software & monitoring tools under development

Organisation of discussion to define breakdown of projects for joint ATLAS/LHCb posts: Both ATLAS & LHCb have s/w week beginning of March

Await outcome of LCG RTAGS: Software management Persistency solutions (Maths libraries) …


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Grid Software TestsGrid Software Tests

• Working on two fronts: European tests under auspices of EDG WP8 US tests within Griphyn Coordination between projects is critical, or we run a serious risk of

divergence (or having to make a choice) We are building up some momentum now

• New overarching CMS GRID subproject set up Coordinator: C. Grandi (Bologna) Task: integrate work on two fronts, set up planning for ~3 years First planning documents now circulating within CMS The UK has an important role, through manpower and facilities

• UK involvement Mostly through IC WP8 manpower so far (Phil Lewis) Bristol WP8 effort (Owen Maroney) coming on line now!


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Grid Software Tests(2)Grid Software Tests(2)

• EDG tests: See EDG 8.2 deliverable for details At the “hello world” stage – beyond this, problems with stability of

CERN testbed A long long way from “production” use The setup seems somewhat fragile and “baroque” (uninformed

personal comment!) – but the feedback to WPs is so far working OK• Griphyn tests:

See Griphyn reports for details Mostly ‘demonstrators’, which have worked well (long past “hello

world”, but certainly not production) Plans to tie remote sites together for upcoming production using

CONDOR-based ‘MOP’ tool.• Not as much GRID-based production-quality software as we

hoped We all suffer when the project slips


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MC ProductionMC Production

• Past involvement The UK has contributed ~20% of production capacity up until now No mean achievement, given size of resources (we are efficient) Very demanding of manpower – needed to address this.

• “Feb 2002” production (~20 TB / 150 CPU-year level, 20 sites) Starting now! Providing “real” MC data for PRS groups (NOT an

“MDC”) The UK hopes to contribute at ~20% level again

• Probably optimistic, as we are in advance of the T1 hardware arriving All new production system and central DB (IMPALA / BOSS) UK Centres involved: RAL (CSF++); IC (JREI farm); Bristol (group

farm)• Data movement will be managed through ‘old’ Globus1-based GDMP• Why? Failed to make Globus2-based version work at “production” level

See circulated document for details + assessment of “real” T1 demand

• Many thanks to T1 staff for addressing some of these problems The WAN network is a problem (and we are investigating this with

R. Tasker)


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Posts & PlansPosts & Plans

• Posts (WP8): IC: P. Lewis (generic WP8) - functional; 0.5 FTE (GRID production

system) – filled (Barry MacElvoy) Bristol: 0.5 of O. Maroney (generic WP8) – just starting; 0.5 FTE (GRID

object data access, split with BaBar) – recruiting (also thanks to M. Kelly)

Brunel: 0.5 FTE (monitoring / T1 simulation) – recruiting Next step is to start some UK coordination (including S. Burke)

• Plans: Concentrate on 2002 production (C. Mackay, D. Newbold coordinating) Participate in continuing EDG WP8 work, relying on GridPP for support Examine how new effort is best managed (e.g. links into the

interesting LCG RTAG project for Bristol effort) Using GDMP between IC farm & SE at LeSC Integration of IC system into testbed

• The future looks bright! But we need to start some intensive technical discussion within GridPP

now the way forward is clearer… (via EB)


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ATLAS GridPP Funded PostsATLAS GridPP Funded Posts

• First Tranche, 1.5 posts:–RHUL post, filled (Mike Gardner), to work in Installation Tools with Glasgow, UCL

–Cambridge (GridPP/CeSC – Frederic Brochu) • Second Tranche, 2 posts:

–Birmingham post to work on Grid MC production system• RG2 approved, about to advertise• Will co-ordinate with Ganga posts

–Two Ganga posts shared with LHCb (Oxford,Cambridge)• Details of tasks need to be discussed – ATLAS/LHCb centrally

• ATLAS Grid Integration meeting first week of March (All groups should send post-holder or a representative)

–Contacts already with US/Italy/LHCb on Installation Tools etc–Discussions ongoing on Ganga co-ordination

Non-GridPP Funded PostsNon-GridPP Funded Posts• Many sites have Globus installed in

different versions• Release 1 ATLAS verification

awaiting 1.1 release– Glasgow already involved in

testing 1.0, Lancaster and Birmingham declared intended involvement with 1.1. Other sites have attempted 1.0 installation.

• Birmingham have been working on the LFNs and general database work

• Glasgow, UCL already working on the Installation Tools

– Meetings with LHCb and contact made with US and Italian workers

• Oxford to have a lecturer post that will work on ATLAS/Grid to start October 2002

• Cambridge (through CeSC) have a system manager for setting up a cluster in HEP for ATLAS/LHCb DC & EDG TB work

• DCs the highest priority– Lancaster have been

making the DC0 jobs scripts, verification histos and have run 2/3 of the production (full and fast simulation)

– Other sites have installed and tested the early ATLAS installations and run Fast simulation samples

– Cambridge have PD Fellow for DC work (+student)

ATLAS NeedsATLAS Needs

• Immediate needs all driven by DC1• DC1 in two phases

– April 15-end July, High Level Trigger MC production 50% in July

• Large (100 cpu) sites for main production, ~25 Gb per cpu

• 600/1000 cpus away from CERN – RAL + Lancaster (+ MAP?)

• Data available to CERN jobs until end of year (could be shipped elsewhere)

• Smaller site physics productions (or present as single resource?)

• Require:– Atlas software release 3.0.0 (kit available mid-March)– EDG middleware (release 1.x)– ROOT – Objectivity server at major sites. (Objy may not be needed at

all in phase1, depends on progress)– Sites without Objy can do generation/simulation, but

reconstruction may have problems


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ATLAS Needs(2)ATLAS Needs(2)

• Phase 2 September-December 2002

– Aim is to test the computing model, extensive use of Grid tools for production and analysis; physics samples

– Need for more large site productions and smaller sites doing verification/alignment/analysis etc

– Testing of persistency may need other persistency software (Objy certainly needed at main sites in phase 2)

– Detailed planning in March, including identification of regional co-ordination (ATLAS-UK will address this next week)


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• Currently UKQCD – Generates primary data on dedicated supercomputers – Stored on the rather slow + unbacked up mass storage system

at EPCC (to be decommissioned September 2002)– Analysis + production of secondary data carried out on a

variety of facilities• New JIF funded Teraflops computer (QCDOC) begins

production in 2003– Requires suitable (much larger) data storage and processing– Will generate many terabytes of data– Involves multinational collaborations

• The project has 2 parts– Develop a datagrid supporting distributed data management

across four UK sites: Swansea, Liverpool, Edinburgh, Glasgow• Will replace the current central datastore from September 2002

– Develop a metadata catalogue + corresponding XML schema

UKQCD


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• Datagrid– UKQCD data will be stored in a distributed fashion using disk

farms at different UK sites– Underlying data-grid software is EDG

• Metadata catalogue– In addition QCDgrid aims to associate metadata with each data

set, e.g. a lattice QCD gauge configuration– An XML document for each data set conforming to a schema– XML documents will be stored in a metadata catalogue

• XML schema – Already mainly developed by UKQCD, expected to evolve with

time– Metadata catalogue will deal with varying schemas (within

constraints)• Web based catalogue interface

– Will query catalogue for current schema, generate a search form based on this

– Will form part of an extended browser that queries the datagrid

QCDgrid


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The Project

• Funding: 1 FTE for 3 years from January 2002– Stephen Rutherford, EPCC began work in January 2002– Currently investigating EDG and setting up a test bed

system

• Deliverables– Data Catalogue - June 02– Datagrid Implementation - September 02– Web Portal - April 03– Distributed Analysis - Dec 03

• Who we are– Stephen Rutherford, Matthew Egbert, Andrew Jackson,

Stephen Booth, Lorna Smith

• See: http://www.epcc.ed.ac.uk/research/qcdgrid/• e-mail: [email protected]


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• Experimental support at Tier 1/A centre– Expt volunteer effort– Additional effort coming on line

• Issuing of grants from PPARC– Fixed end date contracts – necessary paperwork from

PPARC is processed quickly

Issues

nick brook university of bristol the lhc experiments & lattice eb news brief overview of the...

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