AMCC 3ware 9000 Series, User Manual

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Maintaining Units
126 3ware 9000 Series Serial ATA RAID Controller User Guide
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 124.
For more information about background tasks themselves, see “About
Background Tasks” on page 119.
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 non-
redundant unit will occur at the same time.
Scheduled Task Duration
If a rebuild completes within a scheduled time, it will not start over come next
schedule time block, unless someone degrades the unit and starts another
rebuild on the unit in the meantime.
Rebuilds occur at the scheduled time when a drive degrades and there is a hot
spare, or when a rebuild has been manually requested. If a rebuild does not
complete in the scheduled time block, it will continue where it left off at the
next schedule time block.
Similarly, if a verify operation does not complete in the scheduled time block,
it will continue where it left off at the next scheduled time block.
Viewing Current Task Schedules
You can see the current schedules for background tasks on the Scheduling
page.
To view the current task schedule
1 Choose Management > Schedule from the menu bar.
The Scheduling Page appears, showing the schedule for Rebuild Tasks.
(Migration and initialization tasks follow the Rebuild Task schedule.)
2 To view Verify Tasks or Self-test Tasks, select it from the drop-down list
at the top of the page.