BaBar

1
BaBars Plans for the Grid

• Chris Brew
• CCLRC Rutherford Appleton Laboratory

2
Aims and Problems

• Aims
• Use LCG to produce significant numbers of MC
  events
• Allow uses to run real analysis transparently on
  Grid Resources
• Problems
• Software
• Data
• Databases

3
Software

• LCG Software model much better for Babar than EDG
• Should be able to copy software releases to NFS
  mounted experimental software areas
• Started to define protocol for bootstrapping
  babar env

4
Data

• BaBar Has a new non-Objectivity Data model based
  on Root files
• BaBar Jobs access data over homegrown xroot
  protocol (now being re-integrated into root)
• BaBar Data registered in MySQL Bookkeeping
  Databases
• Can we add xrootd protocol to SE?
• Can we publish the info from out bbk DB into the
  RLS?

5
Databases

• BaBars Configuration and Conditions DB is still
  Objectivity though work is underway to replace
  this.
• Until then we have two options
• Run only at BaBar sites where we can install an
  Objy Server
• WAN access to centralised objy servers

6
BaBar UK Hardware

• BaBar UK has 7 farms (500 CPUs) at UK
  Universites
• Manchester has been converted to LCG whilst
  retaining access to local software
• Still needs some work on making submission for
  local users easier

7
BaBarUK Hardware Plans

• Plan for roll-out of LCG on BaBar Farms
• Upgrade Farms to RHEL/SL (3 Months)
• Upgrade 1 Farm (Bristol) with LCG (1-3 Months
  concurrent)
• Upgrade all Farms with LCG using GridPP Frontend
  Machines (3 Months)

8
Solutions

• Four Projects
• MC Production on LCG
• Analysis Submission Wrappers
• BaBar Software installation
• BaBar BBK DB and RLS integration

9
MC Production on LCG

• Have MC Production via BaBar framework Globus
  to several UK Farms. Produced gt 20 Million events
• Experiences with that makes us think transfer to
  LCG will not be too hard for sites that already
  have BaBar Software
• Initial tests of this have already started
• Output of BaBar Software installation project
  will feed directly into this as we expand to
  non-BaBar Sites

10
Analysis Software Submission

• BaBar analysis software makes a number of
  assumptions about location and environment
• Needs wrapper utility to bundle up users
  environment and reproduce it before running the
  job
• James Wehner (Man) is working on this, taking the
  experiences from AliBaBar (GridPP1) and is
  producing a full LCG framework

11
BaBar Software Installation

• BaBar Software available at RAL and Man via AFS
  from previous local install
• script in known location to set-up environment
• Need Grid Jobs to
• Install basic BaBar Framework
• Install software release
• Remove Software release

12
BaBar BBK DB and RLS integration

• BaBars new data model and xrootd data servers
  should fit nicely into the Grid infarstructure
• Possible work needed
• Integrating the RLS with the BaBar BBK DB
• Adding the xrootd protocol to the SE
• Not a small job! BaBar BBK has gt100M entries and
  is expected to grow to gt1 Billion by 2010
• Need input from wider BabarGrid Community
• Until this is ready we need a workaround using
  published Tags to locate datasets

13
Conclusions

• BaBar (UK) is putting together a clear plan for
  exploiting LCG
• This will be finalised at BaBarGrid workshop in
  Autumn/Winter
• We have a plan for making our resources available
  to LCG and for making use of others