Problems with cold start

What happens when the code is executed? The assumption is that the code is ready to execute. But

  1. Code may still be on disk, and not even read into memory.
  2. Data may be in slow memory rather than fast (which may be wrong or right for what you are measuring)
  3. Multiple tests often necessary to ensure that cold start effects are not present
  4. Special effort often required to ensure data in the intended part of the memory hierarchy.