Sorry, they've crawled trillions of pages, and narrowed it down to an index of 100s of billions. Conveniently, the link answers your question of "can you have P

Sorry, they've crawled trillions of pages, and narrowed it down to an index of 100s of billions. Conveniently, the link answers your question of "can you have PB sized indices?" to which we can clearly say, yes.