Good concept; lots of design challenges though

Great idea, been looking for something like this for ages as part of our pseudo-HSM. The difficulties in developing a solution must have been huge though! Hope they've worked them all out.

Reliability: Few enterprise arrays will stay in service long enough to see any issues with high rates of spin up/down or load/unload. The vendor will have qualified the disks for this application anyhow and this is an easy one to do an accelerated lifetime test on.

Power: Turning a disk off in and of itself is only a quarter of the story. The biggest impact is really on the need for cooling (and UPS runtime sizing).

Applications: I'm sure the system will profile usage over time and adaptively manage the power policies. The big issue would be the delay in IO completion while the array spins up - perhaps heavy caching is used to relieve the problems caused by high latency IO (effectively a blocking IOP in-thread).

Interesting to see further info on this one..