3Ware 9550SXU-16ML User Guide - Page 186

Chapter 9. Maintaining Units Scheduling Background Tasks You can set up scheduling windows for when background tasks can occur, so that routine maintenance of storage media occurs at times that will be least likely to interfere with peak I/O times. By creating and using schedules, you can limit active rebuilding, verifying, and testing of units to times that are least disruptive. Note: Initialization and migration operations follow the rebuild schedule. Although rebuild/migrate, verify, and self-test tasks are scheduled separately, you set up the schedules for each in a similar way. You can perform the following scheduling tasks: „ Viewing Current Task Schedules „ Turning On or Off Use of a Task Schedule „ Removing a Task Schedule „ Adding a New Task Schedule Slot „ Selecting Self-tests to be Performed Tip: If you want to change a scheduled task, you first remove the scheduled item and then add it back with the desired day, time, and duration. Sometimes you may want to manually start rebuild and verify tasks. For information about how to do so, see the procedures under "Rebuilding Units" on page 181 and "Verifying Units" on page 186. You can also set the rate at which background tasks are performed compared to I/O tasks. For more information, see "Setting Background Task Rate" on page 175. For more information about background tasks themselves, see "About Background Tasks" on page 169. Prioritization of Background Tasks Rebuilding preempts verify operations. If a unit requires rebuilding, that process will take place before the unit is verified. Migration receives higher priority than all other background tasks. 3ware 9000-series RAID controllers can work on multiple units at the same time. This means that if you have both a redundant unit and a non-redundant unit, the verification of the redundant unit and the media scan of the nonredundant unit will occur at the same time. 176 3ware 9550SX Serial ATA RAID Controller User Guide