DaveWentzel.com All Things Data
Heisenberg Uncertainty Principle
relevant when measuring performance on a system.
formulated by Werner Heisenberg in 1927.
When you measure something, there's a factor of uncertainty caused by your measurement.
The more precise the measure of something's position, the more uncertainty there is regarding its momentum (velocity and direction).
When profiling for performance you don't want your tracing activity to cause a perfomrance problem itself.