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Production tools were developed, deployed and used
to manage the work-flow, transfer and replicate data and publish results.
A Web interface to the production database (RefDB) allows
users to get information about available datasets, their location
and to query MetaData associated to them.
No further tools have been deployed to the physicists
to assist them in the subsequent steps of the analysis
(fetching data, building local federations, preparing analysis
jobs, submitting them).
These operations (particularly those related to file transfer
and federation management) requires specific skills and knowledges
and, in some cases, system manager privileges.
The final steps of the analysis see the production of PAW ntuples or root-trees and their interactive analysis using PAW or ROOT.
COBRA provides the possibility to annotate events with
a use defined object (tag) and to store them in collections.
These user-collections have been used mainly to perform fast event-selection
in batch.
Interactive event reconstruction, analysis and visualisation has also
been routinely done using IGUANA.
Analyses has also been performed using Mathematica or Exel starting from root trees.
An interactive environment based on python has been deployed in 2002.
It allows to query, manipulate and loop over event-collections and
the associated metadata.
Access to the full C++ analysis environment was possible by dynamic
loading the corresponding shared libraries.
Full integration with Lizard was provided including interactive
histogramming starting from the event-tag and from the standard
event structure.
Although deployed to physicists in late 2001, no real use
of this environment has been made to produce published results.
The most used interactive environment has been native PAW or Root having
as input files produced in batch.
No work has been performed to integrate the COBRA interactive
environment with either PAW or Root.
A prototype of an analysis client-server environment (Clarens) has been
developed using web services. It included Objectivity, Root and a
RDBMS backends. It uses globus for authentication, authorisation and security.
As any other grid-based tool, it has not been deployed to physicists yet.
The current environment is clearly not satisfactory.
Root itself is seen just as a starting point.
CMS physicists do expect in future to be able to choose
among a multitude of tools populating their desktop.
It is essential that these tools can interoperate with each other.
CMS physicists do expect some sort of common intermediate analysis data format
that can be understood by the CMS framework and all these tools.
There is the clear need to have the full power of the CMS
simulation, reconstruction and analysis software system available in
the interactive environment fully integrated with the analysis
tools.
This environment should also be available for online monitoring.
Mixed feeling exists on the real need to run the exact same algorithms in batch (online or offline) and in interactive analysis. Final analysis code is seen by some physicists as disposable: re-engineering it is considered mandatory if it should be moved to a production environment.
Iguana developers have identified commonalities with
Panoramix LHCb event-display and several features of the latter
that they may wish to implement in IGUANA.
CMS would welcome a collaboration of the two development
teams eventually under the umbrella of the LCG.
CMS physicists share the view that the interactive analysis environment should allow to interact will all components of CMS simulation, reconstruction and analysis software.
Possible common projects: