Using RAID0/1
RAID0/1 uses both RAID0 and RAID1 technologies implemented together
to achieve high reliability and high I/O performance on your disk array.
RAID0 produces a striped drive volume. Striped data means that the stream
of data from the host is split and distributed onto two or more of your disk
devices on a byte or bit basis. RAID0 produces a very high-performance
I/O disk subsystem, where fault tolerance is not required.
RAID1 is a disk-mirroring algorithm that requires at least two disk drives.
RAID1 produces a mirrored drive volume. RAID1 is the simplest of RAID
technologies because of the nature of mirrored storage. The RAID
controller writes the data to both duplex areas of cache. After the first write
to your primary disk is complete, the secondary copy of data in cache is
written out to your secondary disk. After the writes to both disks have
completed, the write cache is released. RAID1 arrays are fault tolerant, but
they have lower performance than RAID0 arrays.
As mentioned earlier, RAID0/1 adds the high I/O performance features of
RAID0 striping to the high-reliability features of mirrored storage of
RAID1. RAID0/1 uses all four disks in an array group for the primary
storage path. The I/O performance improvements are achieved by splitting
the I/O data streams onto all four disks in the array group. Striping the data
across the four disks more than doubles the RAID1 performance.
From figure 13 (page 97), you can see how the primary data is physically
written across all four drives. The diagram also shows how the secondary
portion of the storage array is used for the mirrored copy.
Writes to the array in RAID0/1 mode occur the same as explained for
RAID1. The primary side is destaged first. After the primary data has been
successfully destaged, the secondary data is destaged to the mirror drive
mechanisms.
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HP SureStore E Disk Array XP512/XP48: Owner’s Guide

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Este manual também é adequado para os modelos :
dados de dispositivos de processamento - HP StorageWorks XP512 Disk Array (1.37 mb)