Overhead of sampling a covergroup every clock cycle

*In reply to o-hassan:*There are too many unknowns to answer this predictably.

  1. how complicated is it to figure out when to sample if not every clock cycle?
  2. how complex are your bin expressions?
  3. Is your simulator optimized to turn off the covergroup once it reaches 100% coverage?
  4. and how long into the simulation does that take?

You may just have to try some experiments.