pbs signature check: only sort by filenames, test for initial backup
I think that using
xargs -P4is a bad idea. It's terrible for HDD and counter-productive when the machine has less than 4 cores, and this 2 criteria aren't rare for backup machines. A single core is also often close to SSD speed, or even higher.
Currently, I see a machine with 4 processes in D-state, checksumming at very low speed. It's a VM and I don't know yet what kind of disk it is.
This commit is not the only one adding this flag.
+1 for removing
-P4for checksum operations.
+1, if I remember correctly, I always wanted that background proccess consume as less as possible, this probablly passed unnotice during the review.