Thanks all ...

I already know that the accuracy, when using the CPU-cycles, is an issue and the way to capture it is difficult.

One of the options is to use a trace (another than the default trace - this one is not containing the appropriate info) and stream it into a table using just the right trace-parameters.

When loaded into the table I wil generate a data-report periodically, safe this data in a report-table, and empty the trace table based upon a time-stamp.

Using the CPU (as part of the trace data captured) iso CPU-cycles is another option and pretty accurate regarding CPU use.....

Guus