H. Beker(1), M.L. Ferrer(2), W. Grandegger(2), A. Martini(2)
V. Valente (3)
(1) : CERN-PPE
(2) : I.N.F.N - Laboratori Nazionali di Frascati
(3) : I.N.F.N - Sez. di Roma "La Sapienza"
(presented by : H. Beker)
AbstractThe KLOE experiment uses a parallel event building system based on chains of VME crates with custom Readout Controllers, a FDDI/ATM Gigaswitch and a farm of about 100 processors where complete events are built, reconstructed and written onto a set of tapes, at an aggregate throughput of 50 MBytes/sec. The modular farm housed in an open bus standard crate with a total processing power of about 16000 specint92 will contain both the network interface to VME and high speed peripheral bus interfaces for magnetic media.
The talk will concentrate on the software techniques for interprocess and interprocessor communication between the numerous processors in the system. Processors sharing the same memory as well as network interconnected are addressed. We will try to demonstrate that standard UNIX communications protocols even without the use of specific real time extensions can address many of our needs trying to avoid context switching and 'rendezvous'. These techniques will be demonstrated on the example of a new buffer manager semantics used both in the transport of the main KLOE data stream as well as in monitoring. This solution was triggered by the somewhat recent availability of high level operating systems on front end microprocessors. This has created a new degree of comfort and more important portability for hardware-close real time applications.
Submitter`s name: M.L. Ferrer
Speakers's name: Harry Beker
Submitter`s Institution : I.N.F.N - Laboratori Nazionali di Frascati
Address of the Institution: Via Enrico Fermi 40, Frascati, Italy
Submitter`s email address: ferrer@lnf.infn.it
Submitter's Phone: ++39-6-9403 415
Fax : ++39-6-9403 427
Topic area : (C) DAQ and Triggering