Outline: LHCb and LCG-AA Ph.Charpentier B 00 l e

PhC LCG-AA Internal review2 LHCb Applications Simul. Gauss Analysis DaVinci MCHits DST Raw Data (r)DST MCParts GenParts Event model / Physics event model AOD Conditions Database Gaudi Digit. Boole Trigger Moore Recons. Brunel

PhC LCG-AA Internal review3 LHCb packages dependencies LHCb Online SEALPOOL RootExt.Libs GaussBooleBrunelPanoramixMoore Gaudi LCG Framework Applications PhysRecLbcom Event Model DaVinci Component projects COOL CORAL Geant4 GENSER : depends : uses

PhC LCG-AA Internal review4 LCG-AA dependencies m LHCb applications depend on LCG-AA through Gaudi o Persistency: POOL o Conditions DB: COOL o Event model: physics vectors, SVectors, SMatrix from ROOT P No more CLHEP dependency (new event model) except through Geant4, HepMC o Simulation: Geant4 (Giga), generators from GENSER, HepMC o No direct dependency on CORAL nor on SEAL (but need all libraries…) o Minimum of PI needed integrated in Gaudi m SPI dependencies o Externals: direct dependency (GSL, Boost, Python, Xerces…), plugins (gfal, lfc, castor, dcache…) o LCGCMT for build (LHCb uses CMT) o Savannah for bug and feature tracing P Gaudi, applications, but also DIRAC, GANGA m Platforms used o slc3_gcc323, moving to slc4_gcc34. Windows VC debug version o Interest in MacOS

PhC LCG-AA Internal review5 SPI m LHCb build relies on LCGCMT o Acknowledge CMT interfaces for external projects P Should separate build and runtime dependencies P LHCb script used for setting run time environment for plugins o LHCb would like to be able to rebuild from source (for non- supported platforms) P Might be facilitated by AA using CMT m LCG externals o Very positive, AA flexible for adding new packages m Releases o Tarfiles should be built automatically and systematically o doxytag files should be produced automatically (our doc relies on it)

PhC LCG-AA Internal review6 SPI (cont’d) m Middleware client libraries (part of lcg/externals) o Good (necessary) to have full control of versions P Impossible to rely on Grid-installed versions o Better liaison needed with developers o Why not deploy client libraries only through lcg/externals? P Libraries (gfal, lfc, castor, dcache_client) P Setting the UI environment breaks AA dependencies P … thus release most common LCG commands (already there) d lcg_utils, grid-proxy-init… d need for repackaging (globus comes through globusrls ;-))

PhC LCG-AA Internal review7 Persistency m POOL o No need for File Catalog support besides XML (gfal ROOT plugin) o Stable and reliable o LHCb contributes to storage manager (M.Frank) m CORAL o No direct dependency m COOL o Basis for our Conditions DB o LHCb contributes to COOL Core development (M.Clemencic) o Framework completed for seamless update of calibrations and alignment from Conditions o Migration from XML files to CondDB to take place in coming months P SQLite slice used for simulation P ORACLE DB used at Tier1s & CERN for reconstruction / analysis P Replication through 3D (ORACLE streaming)

PhC LCG-AA Internal review8 ROOT m REFLEX, RELAX used by persistency (+ ROOT IO) and GaudiPython (through PyROOT) m Event model moved from CLHEP to ROOT new vector and matrix classes o Contribution to packages evaluation and SMatrix (symmetric matrices) o Used successfully for DC06 software releases m File access: support for all file access protocols needed o rfio, rootd, dcap, gsidcap o Use gfal for file access and/or file staging (Gaudi event access service) - from LFN, SURL or tURL o Plugins need testing and version control P Problems of server version compatibility? P Client libraries should all be backward compatible P How to back port bug fix releases of plugins (cf rfio recently)

PhC LCG-AA Internal review9 ROOT (cont’d) m LHCb still has legacy data and hence software…. o Uses ROOT 3! o Ported Castor2 plugin to ROOT 3 o Not clear how long this support can go (LHCb would need it until end 2006) m PROOF o LHCb watching developments o Currently considering more batch analysis using Ganga / DIRAC / LCG grid (job splitting, result merging) m Plugin and component model o Convergence needed between SEAL and ROOT. o Gaudi could use it instead of its own (see review 2005) m General remark o Beware to concentrate on LHC top priorities….

PhC LCG-AA Internal review10 Simulation m Simulation production performed on the GRID o all software distributed to the sites  ship only necessary libraries and input data m Almost all generator libraries from GENSER area o HepMC for event record P schema evolution o Generators integrated in Gauss simulation framework o Pythia , LHAPDF 4.2, Photos for DC06 production (PDFLIB in DC04 no longer used) P libraries cannot be removed from LCG area without agreement o Herwig , Hijing 1.383bs not yet used for central productions P work in progress for integration of Sherpa o Private LHCb version of EvtGen (adapted from BaBar) and of BcVegPy P EvtGenLHC in GENSER based on LHCb version o Initial problems with granularity of libraries P better now for remote distributions, could be improved further P at CERN link directly with GENSER areas

PhC LCG-AA Internal review11 Simulation (cont’d) m GEANT4 used in Gauss for production of data for physics studies since DC04 o Version 7.1.p01a used in DC06 o Due to DC06 production Gauss has not yet been ported to version 8.1 o Stable production ongoing m Source taken from GEANT4 area and global libraries built in LHCb with CMT o allow fast bug fixes to be introduced for example for problems identified in production P good communication with GEANT4 team m FLUKA used for radiation studies at CERN o library downloaded from web site

PhC LCG-AA Internal review12 Management and release cycles m Management o Very effective Architects Forum biweekly meetings o Easy to reach consensus for next steps o Need for closer integration of Grid client libraries P LCG developers’ and deployment representative in AF m Release cycles o Improvement with the policy used since spring o Still could be faster for rebuild releases o Tarfiles and doc to be built automatically with releases o Useful to have a preview (LCGCMT_HEAD) o LHCb cannot pick up all releases, but easy to make plans if LCG- AA follows the agreed schedule

PhC LCG-AA Internal review13 Conclusions m LHCb is fully using LCG-AA o All projects, directly or indirectly m LHCb is generally satisfied with the service provided o Efficient organisation o Improved release cycle m Looking forward to better integration of external Grid / fabric software m Ready to face the challenge of real data… when they come