Originally Posted by nleksan
SSD caching doesn't require a RAID array to boost performance, and I would go so far as to say that for probably 99% of things you would not see any difference between a single drive and a RAID array when both are being cached to an SSD. Only when you have files that are too large to fit in the cache or during extremelywrite iintensive operations would the array win.
You do need raid and UEFI booting if you plan to boot from the largest single volume you can create, and then SSD cache it. Obviously you're after capacity if you're using physical disks, and considering a SSD cache because you want this tech to boost performance on that data, so raid10 makes sense for performance & redundancy of a large volume. Who wants to lose terabytes of data due to a broken raid0? raise your hand! Let's here it for raid10!, but yes it's expensive performance storage, you lose 50 percent of your disks in the array to redundancy and the minimum array size is 4 disks...
You will most certainly see a performance increase raid0/raid10 vs a single drive, whether you cache it or not. I just like Raid10 because it offers the best of both worlds, performance and redundancy, cache whatever you like. Go buy a single 4TB drive and UEFI boot it so you can cache the entire thing, but you'd be better off with a raid0 or raid10 made from 4TB drives vs a single drive if you want to maximize performance.
As a note: I believe you will see less "relative" benefit caching raid0/raid10 than caching a single disk or raid1/raid5. For example, if you Google it, there is a write up where they show a cache offering less relative benefit on a VR vs a Black Caviar drive, but absolute speed is absolute speed. Caching a slow disk setup offers a great boost, but you will have an underlying slow disk when the cache needs to go read or write from it.
So from my perspective, if I'm building a single giant volume I don't want the potential of failure from a broken raid0, and I don't want the slowness of a single disk, mirror, or raid5. So I'm going to build redundancy with performance using a raid10, then cache it, and I've got the best hybrid SSD/spinning disk option going.Edited by Undermoose - 3/17/13 at 7:25pm