One word of caution for using the script on unraid 6 with VM's. I ran into issues where the script ran fine, but when a parity check kicked off, it would cause unraid to freeze (looked like a kernel panic, that others were able to resolve by pinning CPU's to dom0, but that didn't help in my case). As soon as I went back to the default values the problem went away, so I'm guessing something was just pushed too far, and the machine ran out of resources during parity checks.