Very slow performance during backup
I noticed it before, and now my server is really slow again during backup.
Every night, when the backup has started, as the command ps aux shows, it uses all of my CPU resources:
root 28054 4.1 0.0 18372 1284 ? D 00:32 0:24 tar pczf /var/backup/web14/web14_2013-07-01_22-32.tar.gz --exclude=backup* --directory /var/www/clients/client3/web14 .
root 28055 86.0 0.0 4092 772 ? S 00:32 8:25 gzip
The virtual server has eight cores with 8 GB memory and I am hosting about 30 not very busy websites. And during the backups the websites are really hardly visible.
Is there something I can do so the performance will not be influenced during the night backup? Maybe I can set the backup to very low priority?