The state of SSD storage for a database server

Rob Mueller – 27 October 2009

Note: The SSD market is moving quickly, so I'm sure by the time you read this, it's probably out of date :)

As mentioned in another post, we're looking for some new servers. These are to replace our existing database servers, which have had a long and productive life (over 6 years). They're still running fine, but they're starting to get a little more loaded than we'd like during backup runs. As an FYI, our database requirements are much smaller than you'd expect for our size. Our database holds information like the user list, domains, aliases, user address book, personalities, signatures, etc, but most of our storage space is used by emails and files, and those aren't stored in the database at all. Because of that, we only need about 20G of storage now.

I'd really like to get some machines that will last at least 3 years, and scale to at least 20x what the existing servers can. To do that, I think we need to look at using SSD technology for storage. Unfortunately the SSD storage market currently presents a whole range of choices, all with their own annoying pros and cons. For the 20x scale, I'm looking at about 200-400G of storage. Looking over them I've found these.

Intel X-25e

Fusion-IO

RamSan-10/20

Sun F5100

Violin Memory

Conclusion

There doesn't appear to be a clear "winning" solution, as usual, it depends on your storage, IO, and cost requirements. When I first heard about Fusion IO, I was initially very excited about what it seemed to offer, but over time, I've become a bit more circumspect given the concerns over durability, system overhead (RAM + CPU), and recovery time requirements. The Sun and Violin options seem designed at considerably higher end (both storage space and cost) systems than what we're looking for. I really wish the RamSan-10/20 had an open source Linux driver. Given TMS have a long history with NVRAM systems, I have a gut feeling of "they know what they're doing", but for us, an open source driver is mandatory. That really just leaves Intel drives in a RAID array at the moment, which is probably what we'll aim for now. By starting with just 2 drives now (very cheap), we can at least replace them in the future with either more, or newer and faster drives, or another solution altogether if it comes along.