000004592 001__ 4592
000004592 005__ 20241112054816.0
000004592 037__ $$aBELLE2-TALK-CONF-2024-128
000004592 041__ $$aeng
000004592 100__ $$aSeokhee Park
000004592 245__ $$aZeroMQ Based Online ROOT-Output Storage and Express-Reconstruction System for the Belle II Experiment 
000004592 260__ $$aReal Time 2022$$c2022-08-01
000004592 300__ $$amult. p
000004592 520__ $$aThe Belle II experiment started to take data of electron-positron collisions provided by the SuperKEKB accelerator, with all subdetectors from March 2019. The Belle II detector consists of 7 subdetectors and data from each subdetector are serialized by event builders. The maximum trigger rate at the detector is designed to be 30 kHz. The collected data are filtered by a software-based trigger system and stored on online storage. After the online storage, an express-reconstruction system is provided for semi-realtime data quality monitoring and event display. In this presentation, we present ZeroMQ based online storage and express- reconstruction framework to achieve stable data flow during operation. Furthermore, a new storage system, capable of storing data directly in ROOT format, is introduced which is helpful to reduce the network bandwidth of output file transfer from online to offline storage and the overhead of offline computing resources.
000004592 8560_ $$fseokhee.park@kek.jp
000004592 8564_ $$uhttps://docs.belle2.org/record/4592/files/BELLE2-TALK-CONF-2024-128.pdf