The time data, CPU and Elapsed, reported in Detector has a difference with the time data reported in MAINVIEW accounting reports. For example, for a specific Plan the accounting detail times are larger in MAINVIEW reports. The accounting times reported in MAINVIEW reports are based on SMF data.
The Detector times include only the times that are used in SQL execution, and are not equivalent to the times which would be found on SMF data. The SMF/MAINVIEW data includes all activitiy that occurred in DB2 for the Thread, which would include Plan/Package allocation, Thread initialization as well as some Detector overhead and SQL execution, so it is expected that the Detector number would be lower that those reported by SMF and/or MAINVIEW, Detector reports only SQL execution.