If you've ever searched for downloadable tools to benchmark drive performance on your Mac, you have probably ended up downloading free applications from Aja and Blackmagic. You may have realized that these applications don't offer an accurate portrait of how your drive will perform with your editing software, but until now they were the only tools publicly available for this purpose. Now there is a freeware alternative that, while still in beta, may offer a much more accurate glimpse of what is going on.
The tool is HD Drive Speed Test, created by my VFX Show co-host John Flowers. John writes in great detail why he created the tool, and what it's doing that the alternatives are not; the basic gist is that pushing raw data back and forth is only an accurate measure for a file copy, not for reading, writing or encoding video, and so his tool creates representative frames using the format you wish to test in order to help you better engineer and troubleshoot your video hardware. I encourage you to read up if you're interested and give this tool a try.