I have an HP RAID controller with a nice big flash cache with which I'm setting up a simple RAID 1 array on two disks. I can configure the strip size (shown equal to full stripe size) of this RAID 1 array.
What does this mean in the context of a simple mirrored pair of disks?
For striped configurations like RAID 0 over two disks or RAID 10 over four disks the stripe size has a clear meaning. Given that in RAID 1 the data is contiguous along the whole of each mirror disk, the same does not apply.
From some testing it appears that higher stripe size leads to greater sequential read performance. Given this I hypothesise that the controller is using the stripe size as some sort of unit of caching, and reading ahead over this stripe. Then for larger stripe sizes the read-ahead effect is greater. Would anyone care to comment on the plausibility of this?