Is Provisioned IOPS Better? Yes, it Delivers More Consistent and Higher Performance IO

Amazon created a whole new class of service with their Provisioned IOPS for RDS, EBS, and DynamoDB. The idea is simple. If you want more performance, you turn a dial up. If you want less, you turn a dial down. A beautifully simple model. You pay for the performance you want, which is different than their previous cloud model, where performance varied, but you paid only for what you used.

The question: Do these higher priced services really work better?

Rodrigo Campos put this question to the test (only for EBS) by running a benchmark he describes in IOMelt Provisioned IOPS EBS Benchmark Results - December 2012.

The result? Yes, AWS Provisioned IOPS Volumes Really Deliver More Consistent and Higher Performance IO:

It is clear that the provisioned IOPS EBS volumes offer a huge performance upgrade when compared to the non-optimized EBS volumes, but as data has to be spread among more underlying disks or systems, it seems that the volume is increasingly more susceptible to performance fluctuations.

Rodrigo has a little more commentary in a Guerrilla Capacity Planning thread:

It seems that Amazon has put a good deal of effort into the latency and performance fluctuation problems.  Provisioned IOPS volumes really do deliver a more consistent, higher performance IO.  That being said, you'll still get some annoying variance on larger volumes. It seems that as volumes grow and data is more and more scattered among the underlying disks, your volumes will be more susceptible to performance fluctuations.

You'll have to decide the value of these improvements for your application, but at least Rodrigo has helped reduce that nagging doubt that you are paying more for the same service. Provisioned IOPS, at least for EBS, really seems to have lower latency, more predictable performance, along with the ability quickly scale up and down without writing more code. An attractive win for Adaptive Architectures and interesting way to think about your own services.