Backup process consume high CPU resources

Hi I am usign the backup option for my virtualmin servers, but I am managing backups of 8 to 30 GB each one (the weekly full backup)… when the backup is working the CPU load is very hight and it must affectt the normal operation of my VPS during the backup process…

is there any form to limit the CPU use and the bandwith used to make some resources free…

I am using SSHFS to store the backup on external VPS…


Did you check how much of CPU is used during the backup? If you notice that backup slows down your website then you should do that during late night or when is least visitors on your site. I know some big sites/forums even turn off some functions during the backup time like new login, search, new topics… and so on.

In case your website become so slow that is unresponsive then maybe you should see with your host if you can buy more CPU power or switch to bigger package. Of course it could be that your node is oversold and /or old hardware and as result is struggling when it comes to more intense operations especially with OpenVZ, but this is just my guessing.


The backups can indeed be resource intensive.

There are a few options you can use to help tweak that though.

In Webmin -> Webmin -> Webmin Configuration -> Advanced Options, check out the settings named CPU priority for scheduled jobs, IO class for scheduled jobs, and IO priority for scheduled jobs. Each of those can make a big impact on how resource intensive the backups are.


tks for your responses…

what value do you recomend?

I have from 60% to 80% cpu resources used in my VPS…

and this is not affect ram memory too?


Those are settings that the kernel uses to determine what kind of priority to give the processes.

The option “CPU priority for scheduled job” is the parameters used by “nice”. I might try setting that to “17” and seeing if that makes a difference.

The two “iopriority” options are parameters used by the “ionice” program. You may want to start just by setting the second option to “7 (low priority)”.