FICON path busy in the 1:1 swap-out
Start with ESCON path busy
Apply difference in data rates (divide by 4.5)
Apply high side of read/write ratio
- for 2:1 or 1:2, multiply by 2/3
- for 0:1 or 1:0, unchanged
- for 1:1, divide by 2
Add in FICON overhead (10%)