Performing a database backup is a task that consumes large amount of resources. If the production system worked from nine to five, Monday to Friday, then we would easily be able to find a maintenance window, which could be used to schedule the costly backup operation. But what about a 24x7 system where it is very hard to find a maintenance window where the backup task must fiercely compete with other processes to gain access to CPU and I/O resources to achieve the task? The answer, so far, is simple, the backup must be done, whatever the price to be paid.

Oracle 10g introduced a nice feature that allows the DBA to launch the backup task reducing system resource consumption. It allows the DBA to control the backup duration so that the backup may take longer but it will also consume fewer system resources.

In the following example a backup operation takes place. As you can see—the first run shows the amount of CPU consumed by the regular backup operation against...