User Manual - A3661-90001

1-42 Planning Disk Unit Configurations
Global Hot Spare
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RAID Performance
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Table 1-5 Relative Performance, Cost, and Availability Compared to an Individual Disk
Physical disk
configuration
Relative read
performance
without caching
Relative write
performance
without caching
Relative cost
per MB of
storage
Tolerance for
single disk
module failure?
RAID-5 group with 5
disk modules
Up to 5.0 Up to 1.25 1.25 Yes
RAID-3 group with 5
disk modules
Up to 4.0 Up to 4.0 1.25 Yes
RAID-1/0 group with 10
modules
Up to 10.0 Up to 5.0 2.0 Yes
RAID-1/0 group with 6
modules
Up to 6.0 Up to 3.0 2.0 Yes
RAID-1 mirrored pair Up to 2.0 1.0 2.0 Yes