LHCb Computing Activities in UKLHCb Computing Activities in UK

• Current activities

• UK GRID activities

• RICH s/w activities

Architecture of LHCb Computing Model

- based on a distributed multi-Tier regional centre

Processing of real data at CERN (production centre)

Regional centre simulation production

Present Facilities:

Liverpool MAP - 300 node facility

RAL NT farm - closed in February after LHCb MC production

RAL CSF facility - 120 node Linux facility

RAL datastore - IBM 3494 tape robot

RAL NT delivered approx 100k RAWH events/week

MAP can deliver ~16k DST2 events/week if dedicated to LHCb

RAL DataGrid Testbed

RAL CSF

120 Linux cpu

IBM 3494 tape robot

LIVERPOOL

MAP300 Linux cpu

CERNpcrd25.cern.ch

lxplus009.cern.ch

RAL (PPD)

Bristol

Imperial College

Oxford

GLASGOW/EDINBURGH

“Proto-Tier 2”

Proposed LHCb-UK “Testbed”

Institutes

Exists

Planned Cambridge

250 PC99

JREI funding ~£0.4M

Prototype “testbed” Architecture

• Based around existing production facilities

• Intel PCs running Linux Redhat 6.1

• Mixture of batch systems (LSF at CERN, PBS at RAL, FCS at MAP).

• Globus 1.1.3 everywhere.

• Standard file transfer tools (eg. globus-rcp, GSIFTP).

• GASS servers for secondary storage?

• Java tools for controlling production, bookkeeping, etc.

• MDS/LDAP for bookkeeping database(s).

Globus been used to remotely submit scripts and run SICBMC

(CERN/RAL/Liverpool)

LHCb batch (PBS) jobs run on RAL CSF via Globus

ongoing investigations of Globus toolkt: globus-rcp, GSIFTP, RAL

datastore as GASS server

work on-going to “open up” MAP for general use i.e analysis type activitites

co-ordinating LHCb external computing - work on-going on baseline

DataModel

work on-going to harness University NT resources

major i/p to Grid PP proposal (most detailed forward look of all UK LHC

expts) - disappointment on the emphasis of final document

GRID Activities

Summary of current UK LHCb resources

2,775 SI95 shared for LHCb between RAL & Liverpool

(the lion’s share being MAP)

will increase due to RAL upgrade to 3,400 SI95 in

March

end of 2001 “Scotch” facility add additional 2,250

SI95

total end of 2001 to 5,650 SI95

by end of 2001 3.5Tb disk space distributed across

RAL/Edinburgh/Liverpool

at RAL an additional 13Tb robotic tape by year end

Estimation of needs by 2003

Assume 10-15% of 2006-2007 resources needed in 2003

& assuming UK contribution 20-25%

10,800-20,250 SI95 needed

7-14 Tb of disk

23-48Tb of “robotic” storage

Figures consistent with “bottom-up” estimation performed at CERN

Factors 2-4 greater than resources available by end of 2001

RICH softwareRICH software

• UK is co-ordinating the s/w effort

• current FORTRAN simulation written by UK

• FORTRAN simulation used in current RICH studies

still (e.g. alignment studies & optimisation wrt T11)

• since TDR move towards OO - UK prominent (e.g.

GEANT4 studies, interfacing current FORTRAN

databanks to OO-framework…)

• investigation of fast RICH reconstruction

Rich simulation with OO software(work just getting underway)

Simulation of testbeam setup – testing of Čerenkov radiation within GEANT4

Interfacing current info. from FORTRAN simulation into OO environment

Interest in photodetector simulation OO environment

Fast Online Rich Particle IdentificationFast Online Rich Particle Identification

• developing complimentary PID algorithm to offline

method for use in online applications

• online PID searches for potential Čerenkov rings for a

single track. Much less computation involved and

therefore faster.

• initial results with algorithm are encouraging and

studies into potential online applications are

progressing.

• possible gains in global PID performance with online

results merged with global algorithm, for example

background suppression.

SummarySummary

• UK in LHCb in prominent position leading Grid effort

• vital momentum remain and built upon through “GridPP” effort

• UK leading position in RICH s/w - UK effort is now moving into OO s/w and use of RICH “online”