In an ideal world, Enterprise Strategy Group analyst Mark Peters would like to see the choice between solid state (SSD) and spinning disk break down like this:
"If all else was equal and you had a choice between stuff that spins and breaks and stuff that doesn't and doesn't, which would you choose?" Peters asked. "If you had a choice between big, spinning, noisy, heat-producing and breakable and not, and all else [even price] was equal, which would you choose?"
Solid state and spinning disk aren't equal by a long shot yet, at least in price, but the question is intriguing enough to inspire storage vendors to develop new enterprise-ready solid-state solutions, and why you may be hearing a lot about a company called Pliant Technology later this year. Both Pliant and Peters see solid state offering enough advantages so that the differences with spinning disk may dwindle over time.
Everything Old Is New Again
It has been 30 years since StorageTek (now Sun StorageTek) developed the first solid-state drive. And while the technology seemingly took a back seat to hard disk drive-based solutions, it has come back with a vengeance as vendors look for new ways to appease and appeal to enterprise customers who demand speed, performance and perfection from storage systems and have become increasingly frustrated with their HDD solutions.
As with any technology, solid-state drives, which come in two flavors, DRAM and Flash-based, have their advantages and disadvantages, especially when compared to HDD technology. On the "pro" side, SSDs start up faster (as no spin-up is required), read and write quickly, are quiet, use less power and produce less heat, are more reliable and tend to deliver consistent performance.
The "cons," to date: they are a lot more expensive (10 to 30 times more than most HDDs, according to Peters or around $15 per GB compared to less than $0.50 for disk drives), have a lower capacity, can be vulnerable in the event of a sudden power loss, have limited write cycles and slower write speeds, and have a lower storage density though vendors (including major players like EMC and newcomers like Pliant) are hard at work coming up with workarounds or fixes or entirely new approaches to these problems.
"There are some write performance [and other technical] issues," said Peters. "But I don't think the technical issues are so severe that they would preclude solid-state technologies becoming relevant in the enterprise space." That's what Pliant and its backers are betting on.
Storage in a Flash
Led by veterans from Maxtor, Quantum, TeraStor, Seagate, Fujitsu and IBM and backed with funding from Lightspeed Venture Partners, Pliant is out to create "a new class of solid-state drive storage devices for enterprise computing markets." Specifically, Pliant is hoping its new Enterprise Flash Drive (EFD) devices will deliver "dramatically higher levels of performance [than HDD solutions] while meeting the growing need for increased energy efficiency and reliability in enterprise computing environments," according to company literature.
According to Pliant CEO Amyl Ahola, a leading problem that data centers face right now is that while the cost of hard disk drives per gigabyte has gone down, so has their overall performance.
"Hard drives have been failing as far as overall performance," he said, which is due in large part to their mechanical nature. "As a result, data centers have had to buy far more hard drives than they need from a capacity standpoint to get the performance that they need ... in terms of I/Os per second, or IOPS."
Some enterprises are over-provisioning by a ratio of 4 or even 10 to 1 to get the capacity and performance they need, said Ahola, which not only increases their total cost of ownership but their potential failure rate.
"The product that we have, which we refer to as an Enterprise Flash Drive, takes that performance bottleneck out of the picture," explained Ahola. "We have a very high performance solid-state, semiconductor-based drive that no longer has an IOPS constraint. So now you can configure your storage based on what your performance and capacity needs really are, without over-provisioning."
Moreover, Pliant's EFD devices have the same form factor, ability to interface with existing drives and systems, and same software and hardware compatibility as HDDs without "the kind of reliability problems that a hard drive or disk drive has," claimed Ahola (due to the lack of moving parts i.e., spinning heads).
He also said that installing the new EFD devices will result in significant power and thus cost savings for enterprise data centers, as the EFDs typically consume only around 8 watts of power (and require only 8 watts for cooling), as opposed to the 18 watts a typical 3.5-inch hard drive uses (plus 18 more watts to cool them). And with data centers over-provisioning by, in some cases, 10 times, that could mean a significant reduction in wattage.
Testing to Begin in Q3
Although Pliant has yet to release a data sheet or product specifications, it is confident its EFD solution, with a "new and advanced" controller and software design, increased I/O performance, inherent reliability and user-friendly form factor will make it an attractive option to OEMs and data center customers when it becomes available in the fourth quarter of 2008.
As for Peters, who had yet to see a Pliant EFD in action or actual product specs, he believes the technology does hold promise, especially if it performs "orders of magnitude better on all the major issues that currently afflict solid-state technologies, being reliability, longevity, price and performance."
The proof, however, will be in the beta testing, which is set to begin later this year.