Contributions to the online software for ATLAS test beam data acquisition system

Full text: The ATLAS experiment is one of four experiments at the Large Hadron Collider (LHC) particle accelerator that is currently being built at CERN and is scheduled to start data taking in 2007. The large amount of ATLAS detector data requires the design of a very efficient Data Acquisition (DAQ) with a three level trigger system. The Online Software is the global system software to configure and control the DAQ, as well as to share information within the DAQ system, it excludes however the processing and transportation of physics data. It has interfaces to the DataFlow system (being responsible for the transportation of the data from Readout Drivers to Mass Storage), to the different triggers as well as to the Detector Readout Crates controllers and the Detector Control System (DCS). The Online Software consists out of three main packages which in terms contain several components - Configuration (Configuration Database, Online Bookkeeper), Control (Run Controller, DAQ Supervisor, Process Manager, Resource Manager, Graphical User Interface), Information Sharing (Information Service, Message Reporting Service, Online Histogramming Service, Event Monitoring Service). The new design of the Online Software is presented in the document Technical Design Report for ATLAS High-Level Trigger Data Acquisition and Controls. In order to study important performance aspects like alignment and calibration as well as to proceed on the way to the final ATLAS DAQ system, a Test Beam Facility at Super Proton Synchrotron (SPS) accelerator at CERN has been setup for the different detectors of ATLAS. In 2003 four out of six sub-detectors of the Atlas detector were using the Online Software for their DAQ system to perform their data taking: the Hadronic Tile Calorimeter (TileCal), the Pixel Detector, the Muon Detector and Semiconductor Tracker (SCT). A combined beam test of all 4 detectors, with more than 20 controllers and running on 30 workstations, was configured and controlled successfully by the Online Software. The full functionality of the Online Software was available for the Test Beam DAQ system and used by the sub-detectors. A system with more than two hundred workstations was used to study the scaling behaviour of individual components and of the integrated system. These activities are providing important feedback into the development cycle. In order to support the Test Beam users, the Online Software includes a Training package which allows the user to learn about the different components of the Online Software and their usage. Furthermore detailed descriptions about the installation and the usage are available at URL http://atlas-onlsw.web.cern.ch/ Atlas-onlsw/training/training.htm. The main functionalities of the Online Software are provided without the need of commercial packages and the software is available for users by download at URL http://atlas-onlsw.web.cern.ch/Atlas-onlsw/download /download.htm The Bucharest group contributed in the design and implementation of some components used in the test beam configuration (Message Reporting System, Integrated Graphical User Interface), in the software releases testing and component integration activities and in the preparation of the documentation and exercises for the Training package. (author)