Re: Silly suggestion
Why should the OS need to know anything? It should just stripe them together as you say, so that big files can be read/written simultaneously from both halves, and small files can be accessed independently on each. It just needs a way to know that both LUNs are really part of the same physical drive so it can stop people trying to mirror them, kind of like how an OS needs to know that two threads are part of the same physical CPU core for scheduling reasons.
It is no different than how you get the best performance from two separate drives - you stripe them together. Except in that case you increase the chance of failure since they are two separate drives whereas in this case it is all one drive so you don't even take the reliability hit.
Now that I think about it, it might just stripe them together internally and present it as one big drive, at least as a default, since that's the only reasonable thing you can do with it anyway. The only reason you'd want them separate is so you can fiddle with the stripe size if you know something about the access patterns and typical I/O sizes.
Biting the hand that feeds IT
