LHCb StatusNovember2008

PhC 2

Core Software (Gaudi)

m Stable version was ready for 2008 data takingo Gaudi based on latest LCG 55ao Applications ready for using survey geometry,

conditionsDBP Still difficulties in commissioning CondDB access at

Tier1sm Plans for the shutdown

o Use opportunity for “cleaning” part of the framework

P Unifying some interfaces, remove obsolete parts…P Workshop with ATLAS 2 weeks ago…

o Merger with ATLAS on “configurables”P Python-based configuration of applications

o New ROOT schema evolutiono Support file-related records

P Needed for file summary records (luminosity, statistics for skimming etc…)

o More on interactivity (GaudiPython)o Some improvements for Online usageo Studies on multi-core support (parallel file

processing)P In collaboration with LCG-AA / PH-SFT

LHCb Status to LCG-LHCC referees

PhC 3

LHCb recent activities

m Commissioning of DIRAC3o Fully reengineered system (started in September

‘07)o Main features:

P Single framework for services, clients and agentsP Fully integrated Workload and Data Management

SystemsP Supports production and user analysis activities

d Allow to apply VO policy: priorities, quotas…P Uses pilot jobs (as DIRAC2)

d Ready for using generic pilot jobs (not switched on yet)d Full scale test with generic pilots will take place in the

coming weeksP New integrated bookkeeping system

m Production activities (fully DIRAC3)o Complete simulation and stripping of MC data (so-

called DC06 as was launched in 2006)o Start 2008 simulation

P Mainly for alignment and calibration studiesP Physics studies (as of January, currently certifying

Geant4 9.1)P FEST’09 preparatory phase (see later)

LHCb Status to LCG-LHCC referees

PhC 4

Cosmics and first beam data

m Cosmics used for detector commissioningo Of course very few detectors are hit!o Allows internal time alignment of subdetectors

P Using consecutive 25ns slotso Partially time alignment between detectors

P Shifting timing by 12.5 ns and equalising population in consecutive bins…

o All subdetectors included in global runs as of end August

m TED datao LHCb was first to see tracks coming from the

injection line!o Single shots with ~2 muons/cm2, but once every 48

ns!o First tracks in the VeLoo Allowed rough detector time alignment (~2ns)

m 10th Septembero Only muons, calorimeters and short time OT

LHCb Status to LCG-LHCC referees

PhC 5

First data

LHCb Status to LCG-LHCC referees

PhC 6

DIRAC3

m DIRAC3 will be fully ready for first datao Analysis is being migrated

P End of 2008: no LCG-RB needed o Since end of September: no dependency any longer on

SRM v1m Still to come:

o Glexec on worker nodesP Will allow to exploit the full power of DIRAC

d Allows late binding of jobs, VO policy etc…P Running analysis jobs with higher priority without site

interventionP DIRAC3 model was certified long ago by the GDB working

groupP Waiting for middleware to be ready (SCAS service)

o Commissioning of the alignment and calibration loopP Setting up an LHCb-CAF (Calibration and Alignment

Facility)d Requirements are rather modest (“simple” detector)d Start with 2 8-core machines, 200 GB of disk

P Full commissioning of Conditions Database update and streaming

d Currently very few commits to CondDBLHCb Status to LCG-LHCC referees

PhC 7

DIRAC3 jobs

LHCb Status to LCG-LHCC referees

PhC 8

DIRAC3 portal

PhC 9

Recent issues encountered

m Storageo Instability of SEs, in particular dCache

P Very good response from sites and dCache developersP Permanent struggle due to various causes:

d Software issues (addressed with sites and developers)d Sub-optimal hardware configuration at some Tier1’sd Unavailability of files: are in the namespace at site but

cannot be accessed or even get a tURL Damaged tapes, unavailable servers…

o Transfers are OK (low throughput needed: 70 MB/s)m Workload Management

o Three severe issues with WMS (fixes being certified)P Mixing up credentials of jobs submitted by the same

user with different rolesP Limitation in proxy handling (too few delegations

allowed) preventing some users to run jobs (e.g. from French CA)

P Misbehavior of WMS after some idle time: cannot find suitable sites even for a job without requirements!

m Issues with local shared software repository at sites

o Stability and access rights (being addressed)LHCb Status to LCG-LHCC referees

PhC 10

LHCb Computing Operations

m Production managero Schedules production work, sets up and checks

workflows, reports to LHCb operationsm Computing shifters

o Computing Operations shifter (pool of ~12 shifters)P Covers 14h/day, 7 days / weekP Computing Control room (2-R-014)

o Data Quality shifterP Covers 8h/day, 7 days / week

o Both are in the LHCb Computing Control room (2-R-014)

m Daily DQ and Operations meetingso Week days

m Grid Expert on-callo On duty for a weeko Runs the operations meetings

m Grid Team (~6 FTEs)o Shared responsibilities (WMS, DMS, SAM,

Bookkeeping…)LHCb Status to LCG-LHCC referees

PhC 11

FEST’09

m Aimo Replace the non-existing 2008 beam data with MCo Points to be tested

P L0 (Hardware trigger) strategyd Emulated in software

P HLT strategyd First data (loose trigger)d High lumi data (b-physics trigger)

P Online detector monitoringd Based on event selection from HLT e.g. J/Psi eventsd Automatic detector problems detection

P Data streamingd Physics stream (all triggers) and calibration stream (subset

of triggers, typically 5 Hz)P Alignment and calibration loop

d Trigger re-alignmentd Run alignment processesd Validate new alignment (based on calibration stream

LHCb Status to LCG-LHCC referees

PhC 13

FEST’09 runs

m Description of the activityo Define FEST conditionso Start a run

P Events are injected and follow the normal patho Files export to Tier0 and distribution to Tier1s

P CCRC’08 repetitiono Automatic reconstruction jobs at CERN and Tier1s

m Short test periodso Typically a weeko Depending on results, take a week interval for fixing

problemsm Vary conditions

o L0 parameterso Event rateso HLT parameterso Trigger calibration and alignment loop

LHCb Status to LCG-LHCC referees

PhC 14

2009 resources

m No reason to change drastically the overall amount of data

o Real dataP Split year in two parts:

d 0.5 106 s at low lumid 4 106 s at nominal lumi (2 1032)

P Trigger rate constant: 2 kHzo Simulation: 2 109 events

m New assumptions for (re-)processing and analysis o Lack of experience from 2008 non-data

P More re-processings in a first instance in 2009P More calibration checks (done at Tier0)

o Envision more analysis at CERN with first dataP Increase from 25% (TDR) to 50% (first part) and 35%

(second part)P Include SW development and testing (LXBATCH)

o Almost same events sizes and processing times as in TDR

P Small adjustments due to more precise estimatesd Some up, some down…

m Need to account for non-flat usage of resources…LHCb Status to LCG-LHCC referees

PhC 15

Conclusion

m Due to lack of 2008 real datao Use MC data for further testing the whole systemo FEST’09

P Full system test including HLT, online monitoring, streaming etc…

P Short periods (one week) from January to MarchP More FEST in May if no beam

m 2009 real datao Use TED runs (as soon as SPS is running)

P Allows completion of calibration and alignmento First pilot run

P Equivalent to 2008 runP Useful for detector understanding / tuningP First physics results expected even with 108 events

o Nominal (LHCb) luminosity run P Assume 4 106 seconds

m Resource needs are being re-evaluatedo Minor changes except for CERN CPU (3 MSI2k)

LHCb Status to LCG-LHCC referees