Adaptec MAN-00005-UG, Installation And User Manual

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96 Spheras Storage Director Installation and User Guide
Type the amount of available capacity for this logical drive. If your total configuration has only one logical drive that
uses all available capacity, the default sizes should not be changed. If you intend to create additional logical drives, enter
a smaller number to reserve the desired capacity. The Array Usage pie chart indicates how the capacity is being used.
Select Write Cache if you want this logical drive to use Write Back Caching. Write Back Caching improves
performance, but puts data at risk. You should have a battery backup unit or uninterruptible power supply if selecting
this option.
Select a stripe size. If this is a new configuration, this is an editable drop-down list. A change to one logical drive’s
stripe size is reflected by all other logical drives. Smaller stripe sizes provide better performance for random I/O; larger
stripe sizes provide better performance for sequential transfers.
The Cache size is displayed for information only. For external controllers, the cache size and stripe size are the same.
The cache size represents the size of the data in controller memory that is read or written at one time.
Select Enable Foreground Initialization to start the initialization when you exit this Wizard. This check box is
displayed only if the “Background Initialization” controller property is turned off.
With the size of system drives growing dramatically, a traditional initialization (foreground initialization) takes several
hours to complete. The system drive is not accessible during a foreground initialization. Foreground initialization limits
the number of simultaneous initializations to eight. Canceling a Foreground initialization cancels all foreground
initializations (see 6.8 Monitoring Long Operation Tasks on page 128 to cancel a Foreground initialization).
When you are done configuring all of your logical drives, click Refresh to see the configuration changes reflected.
Click Next or the Host/LUN Mapping tab to continue your configuration. Or Click Delete to delete the logical drive and
start over.
The Host/LUN Mapping Tab displays.