A New Event Builder for CMS Run II

21st International Conference on Computing in High Energy and Nuclear Physics

物理学;计算机科学

Albertsson, K.^2 ; Andre, J.-M.^5 ; Andronidis, A.^2 ; Behrens, U.^1 ; Branson, J.^4 ; Chaze, O.^2 ; Cittolin, S.^4 ; Darlea, G.-L.^6 ; Deldicque, C.^2 ; Dobson, M.^2 ; Dupont, A.^2 ; Erhan, S.^3 ; Gigi, D.^2 ; Glege, F.^2 ; Gomez-Ceballos, G.^6 ; Hegeman, J.^2 ; Holzner, A.^4 ; Jimenez-Estupiñán, R.^2 ; Masetti, L.^2 ; Meijers, F.^2 ; Meschi, E.^2 ; Mommsen, R.K.^5 ; Morovic, S.^2 ; Nunez-Barranco-Fernandez, C.^2 ; O'Dell, V.^5 ; Orsini, L.^2 ; Paus, C.^6 ; Petrucci, A.^2 ; Pieri, M.^4 ; Racz, A.^2 ; Roberts, P.^2 ; Sakulin, H.^2 ; Schwick, C.^2 ; Stieger, B.^2 ; Sumorok, K.^6 ; Veverka, J.^6 ; Zaza, S.^2 ; Zejdl, P.^2

DESY, Hamburg, Germany^1

CERN, Geneva, Switzerland^2

University of California, Los Angeles

CA, United States^3

University of California, San Diego

CA, United States^4

FNAL, Chicago

IL, United States^5

Massachusetts Institute of Technology, Cambridge

MA, United States^6

关键词: Aggregate throughput;    Computing hardware;    Data acquisition system;    Ethernet technology;    Full-scale production;    High-level triggers;    Large Hadron collider LHC;    Performance measurements;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/664/8/082035/pdf
DOI  :  10.1088/1742-6596/664/8/082035

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

The data acquisition system (DAQ) of the CMS experiment at the CERN Large Hadron Collider (LHC) assembles events at a rate of 100 kHz, transporting event data at an aggregate throughput of 100GB/s to the high-level trigger (HLT) farm. The DAQ system has been redesigned during the LHC shutdown in 2013/14. The new DAQ architecture is based on state-of-the-art network technologies for the event building. For the data concentration, 10/40 Gbps Ethernet technologies are used together with a reduced TCP/IP protocol implemented in FPGA for a reliable transport between custom electronics and commercial computing hardware. A 56 Gbps Infiniband FDR CLOS network has been chosen for the event builder. This paper discusses the software design, protocols, and optimizations for exploiting the hardware capabilities. We present performance measurements from small-scale prototypes and from the full-scale production system.