Mirrored Disk Arrays; Raid 10 Arrays Maximize Performance And Fault Tolerance; Figure 2. Raid 1 Configuration Example - 3Ware 7000-2 - Escalade RAID Controller User Manual

3ware Escalade ATA RAID Controller User Guide

Figure 2. RAID 1 Configuration Example

TM
TwinStor Technology adds performance
to 3ware's mirrored disk arrays
Traditional mirroring techniques do little to improve performance.
The adaptive algorithms found in 3ware's TwinStor technology
boost performance by distinguishing between random and sequen-
tial read requests. For the sequential requests generated when
accessing large files, both drives are used, with the heads simulta-
neously reading alternating sections of the file. For the smaller ran-
dom transactions, the data is read from a single optimal drive head.
Raid 10 arrays maximize performance and
fault tolerance
When drives are configured as a striped mirrored array, the disks
are configured using both RAID 0 and RAID 1 techniques, thus the
name RAID 10 (see Figure 3). A minimum of four drives are
required to use this technique. The first two drives are mirrored as a
fault tolerant array using RAID 1. The third and fourth drives are
mirrored as a second fault tolerant array using RAID 1. The two
mirrored arrays are then grouped as a striped RAID 0 array using a
two tier structure. Higher data transfer rates are achieved by lever-
aging TwinStor and striping (64K, 128K, 256K, 512K or 1M) the
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