Due to i5/OS restrictions, you can gain the greatest benefit by designing a strategy that combines concurrent and parallel backup support. You should, if possible, use concurrent backups to reduce backup windows for objects which can only be saved using serial mode; such as system data, security data, configuration data, or folders and documents. Use parallel support when you want to reduce your backup window for large libraries and objects, large directories and files, large spooled files, or large numbers of these objects. You can find more information about performing concurrent and parallel backups in Sample Backup Scenarios: Working with Multiple Control Groups and Shared Devices.