f5771a61_12__Storage_Subsystem___Part_2__1
[0] · Mirroring (RAID 1) [1] 
Mirroring is a RAId configuration in which each logical block exists on two or more physical disks.Mirroring often has worse bandwidth and latency for write operations when compared to striping or JBOD because data must be written to a pair of physical disks. It can offer faster read operations than striping because it can (depending on the controller) read from the least busy physical disk of the mirrored pair.It is the most expensive resiliency scheme in terms of physical disks because half (or more) of the disk capacity stores redundant data copies, however, a mirrored array can survive the loss of any single physical disk.Do keep in mind that mirroring has greater power requirements than a non-mirrored storage configuration. It doubles the number of disks; therefore, it doubles the required amount of power.
Performance Tuning Windows 2012: Storage Subsystem - Part 2
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