When Time Duration data is enabled in Time Duration Control records which process/trigger/ruleset/fc/other is responsible for creating the actual records in the timeduration4* tables ?
Just a note for other people who displayed this message like me. According to Help document timedurationdata background process is responsible to process the raw data. Check the schedule record "Process Time Duration Reporting Data" for this.
Extracts the raw time stamp information from the source tables. Service Manager will process the data and save the change metrics in the intermediate tables, for example, in the timeDuration4probsummary table.