Single-Drive Performance with SoftRAID 5

RAID 1+0 uses a striped pair of mirrors for a higher degree of fault tolerance than RAID-5; at least one drive can fail and possibly two (depending on which drives fail).

The spike at end has to do with either OS X or drive block mapping behavior. These hard drives are very fast and represent very high performance for hard drives. One of the eight is a laggard.

The decline in speed over the capacity is as expected for hard drives (rotational data density).

Tested with DiskTester on the late 2013 MacBook Pro in dual OWC Thunderbay enclosures, each on its own Thunderbolt port.

disktester run-area-test --iterations 5 --test-size 4G --delta-percent 5

RAID-5 vs 3X RAID-0 stripe vs 4X RAID-0 stripe
disktester run-area-test --iterations 5 --test-size 4G --delta-percent 5

Eight 5TB drives each initialized as a single volume