SSDs Through a Critical Lens


Expect to see a growing number of servers with on-board solid state drives (SSDs) this year and next as the demand for both faster throughput and lower cost operation kicks into high gear. HP and Sun are talking up plans for server-mounted SSDs, with other vendors expected to follow suit relatively quickly as the cost of traditional magnetic storage continues to rise.


But questions are being raised as to whether SSDs can live up to their promises, and even if they do, whether loading them directly onto the server is the best way to use them.


While SSDs might not match overall storage capacities of traditional disks, they are certainly superior for high-throughput environments. As the SSD Gurus point out in this blog, even if you stripe the rotating drives in your array to gain the random IOPS performance of an SSD, latency will only build in the server queue to the point where it will impact the transaction integrity of the database or whatever application you are using. SSDs push the IOPS through without a server queue.


But that simply begs the question, as EMC's Chuck Hollis does in this blog, of why you would want to bury such an efficient storage solution in the server? EMC clearly has a bias in favor of SSDs in the array -- although it's still being coy about its plans for the CLARiiON system -- but the point here is a valid one: Wouldn't SSDs be more valuable to the enterprise as a pooled storage solution?


The claim that SSDs are dramatically more power efficient is also coming under increased scrutiny. While this report from Tom's Hardware compares the impact on notebook battery consumption, it's still interesting that SSDs draw more power than 7200 rpm 2.5-inch drives. SSDs still undercut the 15,000 rpm enterprise drives, but perhaps not by as much as some of us have been led to believe.


The march of SSDs into the enterprise is probably inevitable at this point, but that doesn't mean they are the preferred solution for every configuration or application. Before you deploy, it's probably a good idea to figure out how they are to be used, and then crunch the numbers to see if they will really provide all the benefits you hope for.