The Tracker detector has been operated with cosmic events at the
Tracker Integration Facility (TIF) at CERN. Data are checked via on-line data quality
monitoring tools running at the Tracker Analysis Centre (TAC) which is a dedicated
Control Room with limited computing resources.
Procedures are also developed and executed in real-time to make data officially
available to the CMS community so raw data are firstly converted in a standard
format, then archived on CASTOR storage system at CERN and registered in the
official CMS data bookkeeping (DBS) and data location (DLS) systems.
The local storage available at TAC computers is sufficient to cache incoming data for
about 10 days, and is clearly the best solution for fast-response analyses and DAQ
checks. On the other side, a large community is expected to analyze data taken at the
TAC, and this cannot happen at because of the limited resources.
Data are expected to flow from the TAC to the CMS Tier-1 and Tier-2 remote sites and
to be accessed using standard CMS tools. Once data are registered in the DBS and DLS
they are ready to be transferred in remote sites using the CMS official data movement
tool PhEDEx. This operation requires that data are injected in the PhEDEx transfer
management database to be routed to destination sites; a set of scripts are developed
to perform this operation periodically in order to send data in the sites interested
to analyze them, currently Fermilab, Bari and Pisa.
Official reconstruction in the distributed environment is automatic and triggered in
real-time from a Bari machine by using a set of scripts optimized to run the
ProdAgent tol, just used to reconstruct Monte Carlo simulated data. Data are
reprocessed with the most recent releases and prereleases of the official CMS
software to provide immediate feedback to the software developers and the users. A
parallel reprocessing executed at FNAL with the last package patches
is used to test the performances of the track reconstruction algorithms in real-time
with read data.
Reconstruction, re-reconstruction, calibration and alignment tasks running at remote
sites which requires to access data in the offline database located at CERN are run
by using FroNTier software to access those data remotely.
Automatic end-user analysis of published data is performed via CRAB tool to derive
the distributions of the most important physics variables.
A monitoring system to check all the steps of the processing chain is
also under development. An overview of the status of the tools developed
is given, together with the evaluation of the real-time performance
of the chain of tasks.