how to determine block size when using dd
How do I figure out what the maximum value of bs can be for a given hard drive when using dd to mirror hard drives?
I know there was some math you could plug into python using the output of fdisk to figure out how high a limit you could put on bs= when running dd to speed up a disk to disk copy. It had something to do with not making it so high that the last block didn't hang off the end of the disk.
I can't find it in any of my googling and I don't want to wait for this thing to finish at 512 block sizes...