What's 12 petabytes to Apple?

The massive "digital locker" the company is said to have ordered may not really be that big

Photo: Isilon

A broken embargo by IBM (IBM) and a preliminary report in a relatively obscure online journal triggered a couple dozen headlines Wednesday, most of which expressed shock and awe that Apple (AAPL) might have ordered as much as 12 petabytes of digital storage to host video content on its iTunes store.

According to Storage Newsletter, Apple was one of the largest of a list of 181 clients for a new product set to be launched next week by Isilon, a Seattle-based maker of clustered storage systems acquired last fall by EMC Corp. (EMC). Apple is known to be building a massive and somewhat mysterious server farm in Maiden, N.C., and anything that sheds light on its size and function tends to make news. (See Apple data-center dreamin'.)

A petabyte -- a unit of information equal to a quadrillion bytes, or 1,000 terabytes -- is a big number. But given that Apple's server farm is supposed to be one of the largest on the planet, is 12 petabytes really that impressive? One video game streaming service, Valve's Steamworks, delivers nearly three times that much data every month, and Google processes more than double that every day.

To put Apple's reported purchase in context, the petabyte entry in Wikipedia offers some illuminating benchmarks:

• 60 petabytes: Storage capacity of the German Climate Computing Center in 2009
• 50 petabytes: Claimed capacity of Teradata's (TDC) Database-12 product
• 35 petabytes: Video gaming data delivered by Steamworks during its 2010 holiday sale
• 32 petabytes: Reported capacity of Hitachi's 2004-era TagmaStore Universal Storage Platform
• 24 petabytes: How much data Google (GOOG) was processesing every day in 2008
• 19 petabytes: Amount of data transferred through AT&T's (T) network every day in 2008
• 1.3 petabytes: Space required by a single game -- World of Warcraft -- to store its data.

All this pales beside the $2 billion storage facility the National Security Agency is reported to be building in Utah. Estimates for how much surveillance data it will store range from hundreds of petabytes to one yottabyte, although that second number strains credulity. There are a thousand petabytes in an exabyte, a thousand exabytes in a zettabyte, and a thousand zettabytes in a yottabyte.

Also on Fortune.com:

• Apple's crunch: Was there a leak?
• Survey: 17% of U.S. teens own iPhones
• Apple 2.0 on The Pipeline

[Follow Philip Elmer-DeWitt on Twitter @philiped]