One of the aspects of RAID’ing drives of different makes, models, and performance is that your slowest drive will be your bottleneck.
To aid in identifying your slowest drive, below is a benchmark script.
- Download: http://download.openegg.org/temp/Simple-IO-Test.zip
- There are two example test scripts. The first one benchmarks each drive at time and the other does it in parallel.
Do the individual test first and then the parallel one after.