For four disks, it seems to me that RAID 10 and RAID 01 would be the same thing. If this is true, then what about the controller? Does it affect the data-transfer rate if the controller processes mirroring, then striping, or striping then mirroring (in the case of four disks)?
RAID 10 and RAID 01 are not the same thing and it does matter. RAID 01 is a mirrored configuration of two striped sets. RAID 10 is a stripe across a number of mirrored sets.
RAID 10 provides better fault resilience and "rebuild" performance than RAID 01. Both array types provide very good to excellent overall performance by combining the speed of RAID 0 with the redundancy of RAID 1 without requiring parity calculations.
This was first published in October 2005