Something interesting.... RAID0+1 with 4 HDs provides better performance than RAID0 with 2 HDs in some cases.
Creating the ideal environment for a high-performance RAID array isn't just a matter of grabbing components and putting together a test system. Our workstation-class system with Areca's ARC-1220 SATA RAID controller might be a perfect platform on paper, but it maxes out at less than 500 MB/s interface bandwidth, less than 400 MB/s read speed, and 275 MB/s write speed. Using five hard drives will give you maximum RAID 0 performance for this given system. However, we're sure that a RAID solution on a different platform, or one optimized for RAID 0, could scale up even more. Part 2 of this article will show that the Areca controller has actually been fine-tuned for RAID 5 and RAID 6 operation, not RAID 0 and RAID 1.