The last three years have seen a profusion of PCIe flash card products brought to market, mostly by startups such as Fusion-io, Micron, Meridian, Warp Drive, etc. EMC's February 6 VFCache announcement is the first, but certainly not the last, such announcement from a major hardware vendor. The flood gates are certainly open, with the promise of order-of-magnitude drops in read and write latency.
This profusion of products provides a great deal of choice for users. And choice is good, right? For instance, Fusion-io provides a large capacity product supporting both high volume reads and writes backed by a single-tier, flash-only storage-on-server philosophy which in many ways is a throwback to the architectures of the 1990s. Data redundancy and sharing is provided by copying data between servers. In contrast EMC has smaller capacity cards providing a read-only cache intended as an extension of a traditional disk or hybrid flash/disk storage array into the server. It is intended to hold the 10% of data in most traditional IT environments that gets 90% of the reads.
So who is right here? As Noemi Greyzdorf, VP of strategy & alliances at Cambridge Computer Services writes in her article SSD: Does it belong in the host, the network, or the array? “There is only one answer to these questions: It depends.” A user trying to improve slow response times from the corporate ERP system is probably going to need an entirely different system than a large online retailer concerned about protecting a high volume of transactions from server or connectivity problems. Questions such as do other applications also need to access or supply data, is the environment virtualized, is the data in small or large chunks, who is the user's main storage and server vendor (and what is that vendor's timetable for bringing out flash products), and how many PCIe slots are open on the server complicate the equation.
Flash is expensive, and a wrong decision can cost a user dearly. Nor is flash just an Internet or enterprise issue. SMBs also have performance issues and will need the new kinds of applications that flash will enable. Few users have the resources to develop the expertise to design an optimal system in house, which means that the door is open for consultants, whether they are from big six firms or smaller organizations.
Action Item: Consultancies should start developing expertise and hands-on experience with various PCIe products now to be prepared to help their customers through the often confusing forest of these new products. This is a genuine new opportunity to provide important value to clients of all sizes. And Wikibon, which has been a leader in covering this fast-developing area within storage, is a good place to start acquiring that expertise.