Promise Technology Pegasus32 R6 - Stripe Size

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Promise Technology Pegasus32 R4/R6/R8
RAID 60 – Double Parity + Stripe
The PROMISE RAID 60 combines RAID 6 distributed (double) parity and RAID 0 block-level striping.
RAID 60 can increase performance by reading and writing data in parallel or striping, while
simultaneously providing parity.
PROMISE implements RAID 60 by creating a data stripe across two RAID 6 sets. This creates very
high fault tolerance, two drives in each RAID 6 set can fail without interrupting I/O or loss of data.
A minimum of eight drives are required for a RAID 60, so this option is available on the R8.
PROMISE RAID 60 starts with RAID 6 double parity, then stripes the blocks
RAID60isavailableontheR8.Togureoutthecapacity,multiplythesmallestdrivecapacitybyfour.
So an R8 with 8 2 TB drives has a capacity of 8 TB with a RAID 60.
Advantages Disadvantages
• High Read data transaction rate
• Medium Write data transaction rate
• Good aggregate transfer rate
• Safest RAID level
• High disk overhead
(four drives as hot spares on R8)
• Slightly lower performance than RAID 50
Recommended Applications for RAID 60 include applications that require extremely high fault
tolerance and good I/O performance.