I understand that the part 17.2/317.9 MiB DL means the downloaded size from https://cache.nixos.org, but I don’t know what the part 60.8/1044.9 MiB means. I don’t understand 2/2/215 numbers either. What does 2, 2, and 215 represent?
2/3/215 (varying the numbers to make them distinct) means that the whole job requires 215 copies, 3 are already done and 2 are currently in process.
I think that the 60.8/1044.9MiB refers to the uncompressed size while the 317.9MiB is just the raw downloaded size, but I’m not entirely sure about that.