Visualization of ATLAS TDAQ Phase II Simulations

ATLAS Trigger and Data Acquisition (TDAQ) system will undergo a major upgrade to take advantage of the future High-Luminosity Large Hadron Collider (LHC) scheduled to come into operation in 2029. The complete system will become available only close to the operations date, making it hard to assess candidate solutions. Simulations are used to assess candidate architectures before the real implementation, evaluate the scalability of proposed solutions when real hardware is not available. The simulation produces a wide variety and a large amount of data is in standard format and the visualization of this data is a key task for analyzing the results. Experts need appealing interactive plots that will provide operational summaries, aggregated data, long-term tendencies, correlations, etc. In this context, the present report describes the project, the objective of which was the search, design and development of tools that will help experts to easily and quickly visualize the results of the simulations. The first is called HDFView and it will be a useful tool for exploring relatively small simulations and for debugging purposes. The second one is a tool that consists of three main components: Grafana which is a web application for visualizing data, InfluxDB which is the database where data are stored and a mechanism that transfers data produced by the simulation to the database.