The Facets window has two useful push-buttons:

 

Click on the left-hand blue button || to pause or suspend the operation of Facets. This can be useful when you want to inspect the iteration screen or Facets is slowing down another application. Click on the green > button to resume Facets operation.

 

Click on the right-hand button » to finish iterating at the end of the current iteration. It is the same pressing as the Ctrl+F keys. The button turns yellow. It will return to white when the current processing phase completes.