If I had that link I would have put it here when I made the post. It's just one of many different things I have read while trying to decide how to configure my drives. Which are 4, 2 5tb and 2 4.5tb. I have several 128gb SSD drives. I am guessing I should make the 1 of the smaller drives and 1 of the larger for data, then 5tb for parity and slot 4 for cache. The device is a Lenovo EMC PX4-400D NAS appliance. Thank you.