What does Woz see in solid-state drives?

What does Steve Wozniak know about solid-state drives that we don't? David Flynn, the chief technology officer of SSD start-up Fusion-io, provides some insight into why the Apple co-founder is joining the company as chief scientist.

I talked with Flynn on the phone about what the Salt Lake City start-up, founded in 2006, does and what attracted Wozniak.

Enterprise solid-state drives typically offer much better performance than even the fastest hard-disk drives. Fusion-io claims that its IoDrive improves storage performance by as much as 1,000 times over traditional disk arrays while operating at a fraction of the power and at a tenth of the total cost of ownership.

Flynn offered an analogy to describe what his company hopes to achieve. "The 3D accelerator decimated the vertically integrated companies like SGI, Evans, and Sutherland," he said. "They used to be able to charge hundreds of thousands of dollars for workstations." But inexpensive, off-the-shelf 3D graphics cards from companies like 3dfx, Nvidia, and ATI Technologies in the late 1990s changed all of this, Flynn said.

"The storage accelerator (that Fusion-io sells) is ultimately going to liberate the proprietary storage market," according to Flynn. And Fusion-io is not just whistling Dixie--it has some big backers. Dell was an early investor, and Hewlett-Packard--though not an investor--plans to deploy Fusion-io's drives across its server line, Flynn said. (An announcement that updates the HP deal is coming later this spring.) IBM has also certified the drives for use in its servers.

"We intend to greatly simplify things that have been a bastion of proprietary, high-margin, vertically integrated (storage) companies," Flynn said.

So how will Fusion-io's solid-state drives change all of this? "We have the ability to put five and soon 10 terabytes within a standard 4U server," he said. ("U" is the term used for rack unit in a server, equivalent to 1.75 inches, or 4.45 centimeters.) "In the near future we will be announcing a card which holds two of our I/O memory modules, therefore doubling the capacity but also the performance per slot," Flynn explained.

Flynn continued: "What we're finding is that putting an entire database on silicon has enough benefit, that you don't have to futz around with putting some of it on mechanical disk, some of it on silicon." The company is telling potential buyers to think in terms of $30 per gigabyte.

"We are not replacing a 15K-rpm disk drive," Flynn said. (Hard-disk drives spinning at 15,000 revolutions per minute are the highest-performance disk drives used in enterprise servers.) "We are miniaturizing an entire (storage area network) of multiple drives by making it out of silicon. While a 15K-rpm drive may cost $2 to $3 per gigabyte, a high-performance SAN costs $50 per gigabyte and up--built from those same HDDs, mind you," he said. "Our ioDrives are made up of chips that cost only $2 to $4 per gigabyte, but when we integrate them into a miniaturized silicon SAN, we charge $30 per gigabyte."

Fusion-io's technology is pegged to IOPS (input/output operations per second). And companies such as Citibank and American Express are increasingly looking at server performance through the IOPS lens, according to Samsung, which makes both hard-disk drives and solid-state drives. Enterprise SSDs process 100 times the number of IOPS per watt as a typical 15K 2.5-inch server hard disk drive, according to Samsung data.

Lower power consumption is also a plus. Enterprises solid-state drives consume less than 25 percent of the power of a 15K hard-disk drive, according to data provided by Samsung in October.

Performance and low power consumption, however, aren't enough, according to Flynn. Because enterprise solid-state drives are a relatively new technology, reliability is crucial. Fusion-io offers a technology called "Flashback" protection--extra chips that can jump in to take over immediately if there is a failure. "This is at the chip level. It's not wear-out that's the problem, it's chips that short out" because of the high voltages, Flynn said.

Here are some more specifics Flynn offered. Currently, Fusion-io can achieve just shy of 1 terabyte of storage by using three 320GB cards. "We're doubling density per module and doubling the number of modules per card so we're going to have 1.3TB on a single PCI Express card," he said.

"We'll be able to address 90 percent of the databases with a single drop-in card. Most databases are less than 1TB in size," he said.

And what will Wozniak do? "Not just the visionary part, but involving him in the public eye," Flynn said. "He is (also) helping us change the architecture and focus of our technology."

In a statement earlier this month, Wozniak invoked the potential for "innovation and radical transformation" and said, more prosaically, "Fusion-io's technology is extremely useful to many different applications and almost all of the world's servers."

"SSDs are only the tip of the iceberg," said Flynn. "How silicon will change storage infrastructure...It's a huge thing around messaging and how a disruptive technology will impact all of this."