rclone checksum and rclone check --checkfile hashed one file at a time
unless --download was in use. The non-download branch of CheckSum called
Object.Hash synchronously from inside the listing callback, so --checkers
had no effect there; only the --download branch used the checker token
pool.
Both branches now do their work in the same goroutine bounded by
--checkers, so --checkers means the same thing with and without
--download. Checking a sum file against 2.6 GiB of local files with
--checkers 8 went from 1.70s to 0.31s here.
As a result the "hashing" checking transfer now covers the hashing work
in both branches, rather than being finished as soon as the download
goroutine had been started.
Teddy TennantandNick Craig-Wood
a182fcbce8