Workaround for using rsync in parallel. Joined some ideas from around the web throughout the years, and gave them a deterministic way of ensuring that we know what process is exactly what we want.
prsync uses one rsync thread for each toplevel directory excluding the parent directory '.'
you can pass more directories to exclude via the '-e' option, the directory names should be their fullnames, no regular expressions, and should be separated by commas.
by default prsync will launch four rsyncs, if there are enough directories, of course.
the modes passed to rsync, for the sake of repetition and statefulness are aAHX which will keep user, group, mode, mtimes, acl, extended attributes symlinks and hardlinks.
feel free to contribute to the tool
NOTES
This is designed only for the push use case, not pull, this will copy from a local machine to a remote, as it finds directories through the find command
no extra args passing for rsync are implemented