fastest drumming

According to Metal-Archives, the drummer for Panzerchrist is officially the fastest in the double-bass department...

More evidence from the Metal Observer, in a review of Panzerchrist's album Roomservice...

metal-observer.com said:
While I’m talking about drum beats it feels appropriate to mention that Reno Killerich (The guy who play drums on “Roomservice”, also seen in EXMORTEM), has a world record to brag about. He managed to kick his double bass drums 800 times in 60 seconds, that’s 400 times per foot, which means that he kicked each drum 6.66 times per second, just check on your calculator.
 
More evidence from the Metal Observer, in a review of Panzerchrist's album Roomservice...

While I’m talking about drum beats it feels appropriate to mention that Reno Killerich (The guy who play drums on “Roomservice”, also seen in EXMORTEM), has a world record to brag about. He managed to kick his double bass drums 800 times in 60 seconds, that’s 400 times per foot, which means that he kicked each drum 6.66 times per second, just check on your calculator.

Mike Mallais has the current record of 1034 kicks per minute.

www.mikemachine.ca
 
Fastest blast beats I've heard are on the first Brutal Truth album.

As far as double kick goes, I dunno. Dave Haley from Psycroptic is pretty quick with his feet.