Backups killing server.

[optize]

When backups run, the majority of our servers die completely as pkgacct/cpbackup takes up all the I/O and everything comes to a halt.

As soon as I kill pkgacct/cpbackup, the server goes back to it's normal self.

Is there any way to fix this? Give it a MUCH lower priority on the system? Obviously I need to run backups, however I can't have the server die every 2 days.

It already is set to do incremental backups and no compression.

[m4rc3]

If the IO wait is the problem, you should add another drive just for backups.
That should reduce IO wait a lot.

[optize]

If the IO wait is the problem, you should add another drive just for backups.
That should reduce IO wait a lot.

Yeah, we already do that.

[m4rc3]

Do you guys run anything on that backup drive?

Please paste the output of iostat so we can check the current IO statistics for the server.