The ATLAS DAQ and Event Filter Prototype "-1" Project
Paper: 388
Session: B (talk)
Speaker: Mapelli, Livio, CERN, Geneva
Keywords: data acquisition systems, event building, monitoring systems, data management, ODBMS's
The ATLAS DAQ and Event Filter Prototype "-1" Project
L. Mapelli et al.
CERN, CPPM-Marseille, University of Pavia, University of Bern
ATLAS Collaboration
Abstract
The final design of the Data Acquisition (DAQ) and Event Filter (EF) system for the ATLAS experiment at the LHC is scheduled to start not earlier than 1999.
Clear specification of the detector requirements, further technology
investigation of hardware and software elements and integration studies
are still required to reach maturity for the design. The ATLAS DAQ Group
has chosen to approach such pre-design investigations via a structured
prototype, supporting the evaluation of hardware and software technologies
as well as their system integration aspects.
A project has been proposed and approved by the ATLAS Collaboration for
the design and implementation of a full DAQ/EF prototype, based on the
Trigger/DAQ architecture described in the ATLAS Technical Proposal and
supporting studies of the full system functionality, although obviously
not the required final performance. For this reason, it is refered to as
ATLAS DAQ Prototype "-1".
The prototype consists of a full "vertical" slice of the ATLAS DAQ/EF
architecture, including all the hardware and software elements of the
data flow, its control and monitoring as well as all the elements of
a complete DAQ system, from the detectors Read Out Driver to data
recording.
This paper describes the project, its goals, structure, timescale and
current status. The architectural view of the system and details of its
components are described, namely:
- the Front End DAQ, consisting of the Read Out Board, the local data
collection unit, the interface to the Event Builder and the local DAQ
for the control and monitoring
- the Event Builder, consisting of suitable switching technology supporting
high rate parallel data transmission
- the Event Filter, based on processor farms running an online implementation
of the standard ATLAS reconstruction and physics analysis applications
- the Back End DAQ system, encompassing all the software to do with
configuring, controlling and monitoring the DAQ.
The project also covers issues related to the software development
environment, from the Real Time Operating Systems to databases and
CASE tools.