Speaker
Dr
Vivian ODell
(FNAL)
Description
The CMS event builder assembles events accepted by the first level trigger
and makes them available to the high-level trigger. The system needs to handle a maximum input rate of 100 kHz and an aggregated
throughput of 100 GBytes/s originating from approximately 500 sources. This
paper presents the chosen hardware and software architecture. The system consists of 2 stages: an initial pre-assembly and several
independent Readout Builder (RU builder) slices. The RU builder is based on
3 separate services: the buffering of event fragments during the assembly, the event assembly, and the data flow manager.
A further component is responsible to handle events accepted by the
high-level trigger: the Storage Manager compresses and stores the events on disk at a peak rate of 2 GBytes/s and makes them available for offline
processing. In addition, events and data-quality histograms are served to
online monitoring clients. We discuss the operational experience from the first months of reading out the complete CMS detector.
Author
Dr
Vivian ODell
(FNAL)
