title: Why don't the CPU times in VisualVM add up?
body: <p>I'm doing CPU profiling in VisualVM and look at the results in the call tree.</p>
  
  <p>I have some method, taking a total time X, which is spent in the method itself (Self time), and in subroutines called from the method.</p>
  
  <p>When I add up the times spent in the subroutines, plus the Self time, why doesn't the result equal the total time spent in the method? Note that I'm not talking about milliseconds, but more like 50% or several minutes missing in the balance.</p>