SSDs on a PCIe SAN?

SSDs are making their way into the enterprise in a big way. At the same time, more and more PCIe solutions are being optimized for flash technology.

With that combination, how long will it be before enterprises start deploying networks of solid-state drives that are completely separate from existing hard-drive-populated SAN and NAS infrastructures?

The move toward networked SSDs is initially happening, not surprisingly, on the HPC level. Companies like One Stop Systems are employing PCIe to link up new configurations of server-based GPU/SSD board combinations delivering upwards of 2.5 TB of on-server memory with 80 Gbps connectivity. Using the newest AMD six-core Opterons, the company is able to deliver upwards of 10 TFLOPS of computing power from a 2 U box.

Internal connectivity is one thing, but creating pooled SSD storage outside of traditional storage networking is another. But even here, there are signs of movement.

NextIO, for one, recently signed a deal with Texas Memory Systems that matches the ICA-2800 PCIe expansion chassis with the RamSan Flash drive, delivering a virtual pool of flash storage capable of hitting 15 million IOPS per rack. That package is aimed at application and database acceleration with full error correction and RAID protection, but it’s hard to see why the system could not be easily applied to raw storage needs, particularly for Web-facing, transactional environments.

Then there is Fusion-io, which recently came out with an eight-module version of its ioDrive – the ioDrive Octal – for the federal government. The device, which is built on a PCIe x16 card, provides 800,000 IOPS using 6 GBps connectivity for up to 5 TB of storage. Using an InfiniBand fabric, Fusion-io says you can connect more than 200 Octals together to deliver a whopping 1 TBps.

Will that kind of performance lead people to conclude that SAN/NAS technology is on the way out? Probably not. While there have been limited attempts to pitch PCIe as a full-blown storage network protocol, it would be quite a stretch to imagine enterprises giving up their current plans to consolidate storage on the Ethernet to pursue a PCIe strategy instead.

Nevertheless, there’s every reason to believe that as SSDs become more prevalent in the data center, the need to pool that storage will become paramount. That pooling is likely to take place over traditional SAN infrastructure, but how great would it be to have a complementary high-speed network that can be ready at a moment’s notice for applications requiring lightning-fast I/O?