User Manual

Using the RAID GUI
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• Delete volumes
Select the volume(s) you want to delete and click Delete. To delete all
LUNs of volx, check the ‘Force to delete LUN mapping(s)’ box. All access
to the volume will be stopped.
• Modify volumes
To modify a setting, select a volume and click Modify. Specify the
following options for configuration.
To clear write buffers in the write cache of a volume, select a volume and
click the Flush button.
Name Type a name for the volume ID.
Preferred
Controller
This option is only available when the redundant-
controller system is in use. Select the preferred
controller to be in charge of managing and
accessing the volume. However, the controller
ownership will not change unless you check the
‘Change owner controller immediately’ box.
Write Cache This option enables or disables the write cache of
a volume.
Write Sorting This option enables or disables the sorting in the
write cache. To improve writing performance, it is
recommended to turn this option on for random
access. This option is available only if the write
cache is on.
Read Ahead
Policy
Always: The controller performs pre-fetching data
for every read command from hosts.
Adaptive: The controller performs pre-fetching
only for host read commands that are detected
as sequential reads. The detection is done by read
logs.
Off: If there is no sequential read command, read-
ahead will result in overhead, and you can disable
the read-ahead.
Read Ahead
Multiplier
This option specifies the read ahead multiplier for
the Always and Adaptive read ahead policies.
Select how much additional sequential data will
be pre-fetched. The default value is 8.
Read Logs This option specifies the number of concurrent
sequential-read streams for the Adaptive read
ahead policy, and the range is between 1 and
128. The default value is 32.