User's Manual

128 Controllers
The Patrol Read does not run on a physical disk in the following
circumstances:
• The physical disk is not included in a virtual disk or assigned as a hot spare.
• The physical disk is included in a virtual disk that is currently undergoing
one of the following:
–A rebuild
– A reconfiguration or reconstruction
– A background initialization
– A check consistency
In addition, the Patrol Read suspends during heavy I/O activity and resumes
when the I/O is finished.
To set the Patrol Read mode:
Click the radio button for the Patrol Read mode setting that you want to
select: The possible settings are:
• Auto— Setting the mode to Auto initiates the Patrol Read task. When the
task is complete, it automatically runs again within a specified period of
time. For example, on some controllers the Patrol Read runs every four
hours and on other controllers, the Patrol Read runs every seven days. The
Patrol Read task runs continuously on the system starting again within the
specified period of time after each iteration of the task completes. If the
system reboots while the Patrol Read task is running in Auto mode, the
Patrol Read restarts at zero percent (0%). When the Patrol Read task is set
to Auto mode, you cannot start or stop the task. Auto mode is the default
setting.
NOTE: Refer to your controller documentation for more information on how often
the Patrol Read task runs when in Auto mode.
• Manual— Setting the mode to Manual enables you to start and stop the
Patrol Read when you want using the Start and Stop Patrol Read tasks.
Setting the mode to Manual does not initiate the Patrol Read task. If you
have started the Patrol Read and the system reboots while the Patrol Read
is running in Manual mode, the Patrol Read does not restart.
•
Disabled— Setting the mode to Disabled prevents the Patrol Read task
from running on the system.