apt-get install rsnapshot
/etc/rsnapshot.conf
https://rsnapshot.org/faq.html
Für mich interessant war folgnder Eintrag:
My rsnapshot setup seems to eat the processor on the machines I’m backing up from. How can I prevent this?
rsnapshot itself is a low-overhead program, but rsync can drive processor utilization uncomfortably high. To address this, tell your rsync to run with high nice and ionice values, like 10 and -c3 respectively.
Depending on how rsync was packaged for your system, your installation may have an /etc/default/rsync file. If it does, set RSYNC_NICE and RSYNC_IONICE as recommended. Then restart the rsync daemon. You should notice a difference immediately.
Aber Achtung: Im Kopf von /etc/default/rsync steht:
This file is only used for init.d based systems!
If this system uses systemd, you can specify options etc. for rsync
in daemon mode by copying /lib/systemd/system/rsync.service to
/etc/systemd/system/rsync.service and modifying the copy; add required
options to the ExecStart line.
nice und ionice sind aber KEINE Optionen von rsync sondern eigenständige Progrmme - siehe https://wiki.ubuntuusers.de/nice/ und https://linux.die.net/man/1/ionice
Hier ist beschrieben, wie man es rictig macht https://superuser.com/questions/1148694/nice-rsync-on-remote
Der Aufruf in /etc/systemd/system/rsync.service lautet also:
ExecStart=/usr/bin/nice -n 10 /usr/bin/ionice -c3 /usr/bin/rsync --daemon --no-detach