Dell PowerEdge RAID Controller H700 - Manual (Page 168)

168 Glossary
RAID Level Migration
RAID level migration (RLM) changes the array from one RAID level to another.
It is used to move between optimal RAID levels. You can perform a RLM while
the system continues to run, without having to reboot. This avoids downtime
and keeps data available to you.
RAID Management Utility
A RAID management utility is used to configure physical disks into disk groups
and virtual disks. The BIOS Configuration Utility is also known as
<Ctrl><R>. Use the BIOS Configuration Utility if no operating system has
been installed yet on the controller.
The Dell OpenManage storage management application enables you to perform
controller and enclosure functions for all supported RAID and non-RAID
controllers and enclosures from a single graphical or command-line interface
after you have installed the operating system.
SAS RAID Storage Manager configures, monitors, and maintains the
PERC H700 card, battery backup units, and other devices running on a system.
Read-Ahead
A memory caching capability in some controllers that allows them to read
sequentially ahead of requested data and store the additional data in cache
memory, anticipating that the additional data is required soon. Read-Ahead
supplies sequential data faster, but is not as effective when accessing random
data.
Rebuild
The regeneration of all data to a replacement disk in a redundant virtual disk
(RAID level 1, 5, 6, 10, 50, or 60) after a physical disk failure. A disk rebuild
normally occurs without interrupting normal operations on the affected virtual
disk, though some degradation of performance of the disk subsystem can occur.
Rebuild Rate
The percentage of central processing unit (CPU) resources devoted to
rebuilding. 100% rebuild rate does not mean ALL CPU resources are dedicated
to the rebuild without processing IOs.
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