CMS Tier-0 data processing during the detector commissioning in Run 3.

The CMS Tier-0 system is responsible for the prompt processing and distribution of the data collected by the CMS Experiment. A number of upgrades were implemented during the long shutdown 2 of the Large Hadron Collider, which improved the performance and reliability of the system. In this report, these upgrades are discussed and a more detailed description of the Tier-0 system is given. The experience of the data taking during Run 3 detector commissioning as well as the performance of the system are highlighted. [ABSTRACT FROM AUTHOR]