Ok so here is a really really geeky post. But I feel I had better save it just in case I need to do this again.
If the system performance changes or a different JDK than the calibrated one is used for profiling, the collected performance results may become biased and the profiler needs to be re-calibrated. Unfortunately there’s no UI action available for recalibration in VisualVM, the only way to invoke the calibration again is to manually delete calibration data file in:
and restart the VisualVM.
I need to do this on occasion so I can retake the screenshots of the calibration dialogs. The only way to get them to show up is to do the above.