VME Readout at and Below the Conversion Time Limit
Artikel i vetenskaplig tidskrift, 2019

The achievable acquisition rates of modern triggered nuclear physics experiments are heavily dependent on the readout software, in addition to the limits given by the utilized hardware. This paper presents an asynchronous readout scheme that significantly improves the livetime of an otherwise synchronous triggered Versa Module Eurocard Bus-based data acquisition system. A detailed performance analysis of this and other readout schemes, in terms of the basic data transfer operations, is described. The performance of the newly developed scheme as well as synchronous schemes on two systems has been measured. The measurements show excellent agreement with the detailed description. For the second system, which previously used a synchronous readout, the deadtime ratio is at a 20-kHz trigger request frequency reduced by 30% compared to the nearest contender, allowing 10% more events to be recorded in the same time. The interaction between the network and readout tasks for single-core processors is also investigated. A livetime ratio loss of a few percents can be observed, depending on the size of the data chunks given to the operating system kernel for network transfer. With appropriately chosen chunk size, the effect can be mitigated.

readout

Versa Module Eurocard Bus (VME)

triggers

deadtime

Asynchronous

livetime

data acquisition

buffering

performance evaluation

nuclear physics

Författare

M. Munch

Aarhus Universitet

J. H. Jensen

Aarhus Universitet

B. Loeher

GSI Helmholtzzentrum für Schwerionenforschung

Technische Universität Darmstadt

H. Toernqvist

Technische Universität Darmstadt

GSI Helmholtzzentrum für Schwerionenforschung

Håkan T Johansson

Chalmers, Fysik, Subatomär fysik och plasmafysik

IEEE Transactions on Nuclear Science

0018-9499 (ISSN)

Vol. 66 2 575-584

Ämneskategorier

Datorteknik

Kommunikationssystem

Datorsystem

DOI

10.1109/TNS.2018.2884979

Mer information

Senast uppdaterat

2019-08-20