Users guide

Intel® RAID Software User Guide 334
Consistency check An operation that verifies that all stripes in a virtual drive with a
redundant RAID level are consistent and that automatically fixes
any errors. For RAID 1 drive groups, this operation verifies correct
mirrored data for each stripe.
Consistency check rate The rate at which consistency check operations are run on a
computer system.
Controller A chip that controls the transfer of data between the microprocessor
and memory or between the microprocessor and a peripheral
device such as a drive. RAID controllers perform RAID functions
such as striping and mirroring to provide data protection.
Copyback The procedure used to copy data from a source drive of a virtual
drive to a destination drive that is not a part of the virtual drive. The
copyback operation is often used to create or restore a specific
physical configuration for a drive group (for example, a specific
arrangement of drive group members on the device I/O buses). The
copyback operation can be run automatically or manually.
Typically, a drive fails or is expected to fail, and the data is rebuilt on
a hot spare. The failed drive is replaced with a new drive. Then the
data is copied from the hot spare to the new drive, and the hot spare
reverts from a rebuild drive to its original hot spare status. The
copyback operation runs as a background activity, and the virtual
drive is still available online to the host.
Current Measure of the current flowing to (+) or from (-) the battery, reported
in milliamperes.
Current write policy A virtual drive property that indicates whether the virtual drive
currently supports Write Back mode or Write Through mode.
• In Write Back mode, the controller sends a data transfer
completion signal to the host when the controller cache has
received all of the data in a transaction.
• In Write Through mode, the controller sends a data transfer
completion signal to the host when the drive subsystem has
received all of the data in a transaction.
Cycle count The count is based on the number of times the near fully charged
battery has been discharged to a level below the cycle count
threshold.
D
Default write policy A virtual drive property indicating whether the default write policy is
Write Through or Write Back.
• In Write Back mode, the controller sends a data transfer
completion signal to the host when the controller cache has
received all of the data in a transaction.
• In Write Through mode, the controller sends a data transfer
completion signal to the host when the drive subsystem has
received all of the data in a transaction.
Design capacity Designed charge capacity of the battery, measured in milliampere-
hour units (mAh).
Design charge capacity
remaining
Amount of the charge capacity remaining, relative to the battery
pack design capacity.