Problems with measuring time

  1. Timers are not infinitely accurate
  2. All clocks have a granularity, the minimum time that they can measure
  3. The error in a time measurement, even if everything is perfect, may be the size of this granularity (sometimes called a clock tick)
  4. Always know what your clock granularity is
  5. Ensure that your measurement is for a long enough duration (say 100 times the tick)