Greetings all—I’m Donpaul Stephens, president of Violin Memory
. If you’re not familiar with us, we make memory appliances for applications that demand very high IOP/s or low latency for use in data-center operations. Micron’s Kevin Kilbuck and I were talking the other day and we thought it might be interesting for me to write a quick post on our work with Micron re: the enterprise space and NAND Flash memory.
We started working with Micron a little more than a year ago to leverage their work in NAND flash and look for ways to use those innovations to enable our own plans for our products. Ultimately it’s really a symbiotic relationship where each company can bring requirements, breakthroughs, goals, napkin sketches, all-the-above, to the table to understand the capabilities and (frankly) the wish lists for NAND in the storage space. Through that relationship, we learned about the work they were doing to extend the lifespan of NAND. This was right up our alley--because what they were proposing was a new NAND flash technology that was going to hit one million write cycles. They dubbed it Enterprise NAND
But, before we get to talking too much about Enterprise NAND, let’s talk a little about flash memory in general to provide context to how Violin is using the technology. You’re probably aware that standard flash–both SLC and MLC–has a limited lifetime. If not, here’s a quick overview
: NAND has a given number of cycles (times) that it can be written to before it fails. Standard SLC NAND can be written to up to 100,000 times, which is great for certain applications like mobile phones, for example. Standard MLC NAND can be written to up to 10,000 times, and finds a good fit in devices like MP3 players. Ultimately, both of these variations of flash have ideal applications to call home. But there are still some applications that require longer write and erase cycles, such as with Tier Ø computing which is what Violin’s focused on.
As we looked to optimizations that we could make in our hardware, we identified four fundamental approaches to increase the lifespan of flash-based storage:
1. Improve the efficiency of user writes for the flash media by reducing the write amplification;
2. Improve wear leveling, which ensures individual "erase" blocks are used evenly throughout the system;
3. Increase the capacity of the system, enabling the write load to be spread across more storage;
4. Increase the endurance of the underlying flash devices.
At Violin, we’ve implemented the first three approaches into our system architecture. Micron's Enterprise NAND brings the fourth element to the table. And together, we believe these techniques will dramatically improve the lifetime of flash-based systems, which need to endure the very strenuous write/erase cycles found in today’s data center operations.
We’re thrilled to see Micron extending the lifecycle of NAND and it’s been exciting to be able to work with Micron on such a cutting-edge approach. In fact, we believe extended-cycling NAND to be one of the most important flash memory innovations for enterprise and storage applications. It significantly accelerates the transition from performance disk drives to solid state storage. Stay tuned to see Violin products designed with Micron’s Enterprise NAND in 2009, ensuring a lifetime of reliable data for such applications such as content delivery, e-mail servers and enterprise file storage.