A vast majority of nuclear and particle physicists in the world are currently using the ROOT framework (developed in CERN) as a software platform for simulations and data evaluations. Some of the simulations and experiments performed in this domain are very data intensive and they need to be designed with particular emphasis on the processing performance.
We have analyzed the efficiency of the Background Mixer component employed in particle simulations of the Belle II project and identified, that the ROOT file format is unacceptably inefficient. The structure of the file and the API presented in ROOT framework prevents efficient data retrieval for parallel processing.
We propose a data format which overcomes these limitations and which is much more suitable for high performance computing. We also demonstrate how to integrate this novel format into processing pipeline of the Belle II experiments and present its initial evaluation.