Event builder and level 3 trigger at the CDF experiment

Conference · Mon Jan 01 00:00:00 EST 2001 · Computer Physics Communications

DOI:https://doi.org/10.1016/S0010-4655(01)00261-2· OSTI ID:1898782

Anikeev, K. ^[1]; Bauer, G. ^[1]; Furic, I. ^[1]; Holmgren, D.  ^[2]; Korn, A.  ^[1]; Kravchenko, I.  ^[1]; Mulhearn, M.  ^[1]; Ngan, P. ^[1]; Paus, Ch.  ^[1]; Rakitin, A. ^[1]; Rechenmacher, R. ^[2]; Shah, T. ^[1]; Sphicas, P.  ^[1]; Sumorok, K. ^[1]; Tether, S. ^[1]; Tseng, J. ^[1]; Wuerthwein, F.  ^[1]

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1. MIT
2. Fermilab

The Event Builder and Level 3 trigger systems of the CDF experiment at Fermilab are required to process about 300 events per second, with an average event size of ~200 KB. In the event building process the event is assembled from 15 sources supplying event fragments with roughly equal sizes of 12–16 KB. In the subsequent commercial processor-based Level 3 trigger, the events are reconstructed and trigger algorithms are applied. The CPU power required for filtering such a high data throughput rate exceeds 45 000 MIPS. To meet these requirements a distributed and scalable architecture has been chosen. It is based on commodity components: VME-based CPU's for the data read out, an ATM switch for the event building and Pentium-based personal computers running the Linux operating system for the event processing. Event flow through ATM is controlled by a reflective memory ring. The roughly homogeneous distribution of the expected load allows the use of 100 Mbps Ethernet for event distribution and collection within the Level 3 system. Preliminary results from a test system obtained during the last year are presented.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: CDF
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 1898782
• Report Number(s): FERMILAB-CONF-01-552; oai:inspirehep.net:568476
• Journal Information: Computer Physics Communications, Vol. 140; Conference: CCP 2001; ISSN 0010-4655
• Publisher: Elsevier
• Country of Publication: United States
• Language: English