[ChuckMcM]

And according to the GFS paper their are three copies of every chunk in a GFS cluster so that is 180TB, and they probably don't depend on one GFS cluster to meet their availability guidelines so if you had two that is really 320TB (180TB * 2).

And the amazing part is if you are in an open event where Google is talking about their infrastructure in general terms you will realize that that has to be mouse nuts compared to the amount of 'spinning rust' they have going on at any one time.