Notes / Observer Effect


The observer effect arises when the act of observation changes the outcome.

This term came from physics, here are a few popular examples:

The observer effect should be taken into account when you do benchmarking, testing, or profiling. Let us consider a few more examples from the performance world:

The takeaway here is that when you measure software performance, the observer effect is usually present, so do keep it in mind.


References (3)