Speaker
Marco Pieri
(University of California, San Diego, San Diego, California, USA)
Description
The CMS Data Acquisition system is designed to build and filter events originating
from approximately 500 data sources from the detector at a maximum Level 1 trigger
rate of 100 kHz and with an aggregate throughput of 100 GByte/sec. For this purpose
different architectures and switch technologies have been evaluated. Events will be
built in two stages: the first stage, the FED Builder, will be based on Myrinet
technology and will pre-assemble groups of about 8 data sources. The next stage, the
Readout Builder, will perform the building of full events. In the baseline
configuration the FED Builders merge events from 8 data sources and forward them to 8
independent Readout Builder slices, each made up of 64 Readout Units. The Readout
Units send data to 64 Builder Units that build complete events and send them to PC
farms responsible for the High Level Trigger selection. The finalization of the
design of the Readout Builder is currently under study in view of the installation
and commissioning of the FED Builder and the first slices of the Readout Builder
foreseen in early 2007. In this paper we present the prospects of a Readout Builder
based on TCP/IP over Gigabit Ethernet. Other Readout Builder architectures that we
are considering are also discussed. The results of throughput measurements and
scaling performances are outlined as well as the preliminary estimates of the final
performances. All these studies have been carried out at our test-bed farms that are
made up of a total of 130 dual Xeon PCs interconnected with Myrinet and Gigabit
Ethernet networking and switching technologies.
Primary author
Marco Pieri
(University of California, San Diego, San Diego, California, USA)
Co-authors
Alexander Oh
(CERN, Geneva, Switzerland)
Angela Brett
(CERN, Geneva, Switzerland)
Attila Racz
(CERN, Geneva, Switzerland)
Christoph Schwick
(CERN, Geneva, Switzerland)
Claude Jacobs
(CERN, Geneva, Switzerland)
Dominique Gigi
(CERN, Geneva, Switzerland)
Emilio Meschi
(CERN, Geneva, Switzerland)
Eric Cano
(CERN, Geneva, Switzerland)
Frank Glege
(CERN, Geneva, Switzerland)
Frans Meijers
(CERN, Geneva, Switzerland)
Gaetano Maron
(INFN - Laboratori Nazionali di Legnaro, Legnaro, Italy)
Ichiro Suzuki
(FNAL, Chicago, Illinois, USA)
James Branson
(University of California, San Diego, San Diego, California, USA)
Joao Varela
(CERN, Geneva, Switzerland, LIP, Lisbon, Portugal)
Johannes Gutleber
(CERN, Geneva, Switzerland)
Luciano Orsini
(CERN, Geneva, Switzerland)
Lucien Pollet
(CERN, Geneva, Switzerland)
Michele Gulmini
(CERN, Geneva, Switzerland, INFN - Laboratori Nazionali di Legnaro, Legnaro, Italy)
Peter Rosinsky
(CERN, Geneva, Switzerland)
Robert Gomez-Reino Garrido
(CERN, Geneva, Switzerland, Universidad de Santiago de Compostela, Santiago, Spain)
Roberta Arcidiacono
(Massachusetts Institute of Technology, Cambridge, Massachusetts, USA)
Samim Erhan
(CERN, Geneva, Switzerland, University of California, Los Angeles, Los Angeles, California, USA)
Sergio Cittolin
(CERN, Geneva, Switzerland)
Sham Sumorok
(Massachusetts Institute of Technology, Cambridge, Massachusetts, USA)
Steven Murray
(FNAL, Chicago, Illinois, USA)
Vuko Brigljevic
(Rudjer Boskovic Institute, Zagreb, Croatia)
