Diagnosis
A performance trace can be switched on, on the same instance, eitherfor one user or for multiple users defined using a pattern. It isirrelevant how many performance trace types are used.
In other words, it is not possible, for example, to switch on both anSQL trace for one user and an enqueue trace for a different user.
You are attempting to switch on a performance trace. However, anotheruser has already switched on one or more types of performance traces onthe same instance.

System Response
Processing continues after the error message.

Procedure
You can only switch on the performance trace types you want after alltypes of performance traces have been switched off.
Before switching off the performance trace, contact the user whoswitched on the performance trace. Another user can switch off theperformance trace after a confirmation prompt. Again, it is importantto note that all performance trace types must be switched off.