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SSARAID Command Attributes
When using the ssaraid command, you can specify the following types of attribute:
v RAID array Creation and Change attributes
v RAID array Change attributes
v Physical Disk Drive Change attributes
v Action attributes
RAID Arrays Creation and Change Attributes
This section describes the creation and change attributes that you can use for:
v All RAID arrays
v RAID-1, RAID-5, and RAID-10 arrays only
v RAID-1 and RAID-10 arrays only
v RAID-5 arrays only
v RAID-10 arrays only
Creation and Change Attributes for All RAID Arrays
You can specify the following attributes with the
ssaraid command with the
allow_page_splits=true/false (default=true)
fastwrite=on/off (default=off)
When using the fast-write cache, you can use the following attributes to control the
operation of the cache:
fw_start_block (default=0)
fw_end_block (default=array size)
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User's Guide and Maintenance Information
or
With the attribute set to true:
When large blocks of data are sent to an array, those blocks can be internally
split into smaller, 4096-byte blocks that can then be written in parallel to the
member disk drives of the array. This action greatly improves the performance
of write operations to the array, although the blocks are not written sequentially
to the member disk drives.
With the attribute set to false:
The blocks of data are written sequentially to the member disk drives of the
array. This action can have a negative effect on the performance of write
operations to the array. The sequence in which the data is written to the array
might be critical to the application program that is using the data, if an error
occurs during the write operation.
This attribute enables and disables the fast-write cache.
See the definition for fw_end_block .
This attribute and the fw_start_block attribute control the range of blocks for
which the fast-write cache is enabled. Write operations that are outside the
default range of 0 through array size write data directly to the array, and do not
use the fast-write cache.
option when you are using the
option to create or change a RAID array:
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