User`s guide

22 WebBIOS Configuration Utility
www. del l .c om | s upp ort .d el l. c om
6 Select the Cache Policy.
The Cache Policy determines whether reads for a specific logical
driver use cache memory. It does not affect the Read-ahead cache.
The options are as follows:
– Cached I/O: All reads are buffered in cache memory.
– Direct I/O (default): Reads are not buffered in cache memory.
Direct I/O does not override the cache policy settings. Data is
transferred to cache and the host concurrently. If the same data
block is read again, it comes from cache memory.
7 Enable or disable the spanning mode for the current logical drive.
If enabled, the logical drive can occupy space in more than one array. If
disabled, the logical drive can occupy space in only one array.
For two arrays to be spannable, they must have the same stripe width
(they must contain the same number of physical drives) and they must
be consecutively numbered. For example, assuming Array 2 contains
four disk drives, it can be spanned only with Array 1 and/or Array 3,
and only if Arrays 1 and 3 also contain four disk drives. If the two
criteria for spanning are met, spanning is automatically allowed. If the
criteria are not met, the Span setting makes no difference for the
current logical drive.
8 Select the size of the logical drive in megabytes (MB.)
The maximum size allowed for the RAID configurations displays on
the screen.
9 Click Accept to accept the changes or click Reset to delete the changes
and return to the previous settings.