So you’re tired of watching the grass grow while your Linux RAID2 array rebuilds itself. Let’s take care of it:
$ echo 10000 > /proc/sys/dev/raid/speed_limit_min
This should give you a 10x speedup over the 1000kB/sec default — subject to the limitations of your actual bus bandwidth, of course.
Most useless tip in the world, you are stupid if you actually believe this will speed up the resync