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0 reliability specifications, 1 error rates, 1 recoverable errors – Seagate Cheetah 15K.5 SAS ST373455SS User Manual

Page 21: 2 unrecoverable errors, Reliability specifications, Error rates 5.1.1, Recoverable errors, Unrecoverable errors

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Cheetah 15K.5 SAS Product Manual, Rev. E

15

5.0

Reliability specifications

The following reliability specifications assume correct host and drive operational interface, including all inter-
face timings, power supply voltages, environmental requirements and drive mounting constraints.

5.1

Error rates

The error rates stated in this manual assume the following:

• The drive is operated per this specification using DC power as defined in this manual (see Section 6.2).
• Errors caused by host system failures are excluded from error rate computations.
• Assume random data.
• Default OEM error recovery settings are applied. This includes AWRE, ARRE, full read retries, full write

retries and full retry time.

5.1.1

Recoverable Errors

Recoverable errors are those detected and corrected by the drive, and do not require user intervention.

Recoverable Data errors will use correction, although ECC on-the-fly is not considered for purposes of recov-
ered error specifications.

Recovered Data error rate is determined using read bits transferred for recoverable errors occurring during a
read, and using write bits transferred for recoverable errors occurring during a write.

5.1.2

Unrecoverable Errors

Unrecoverable Data Errors (Sense Key = 03h) are specified at less than 1 sector in error per 10

16

bits trans-

ferred. Unrecoverable Data Errors resulting from the same cause are treated as 1 error for that block.

Seek error rate:

Less than 10 errors in 10

8

seeks

Read Error Rates

1

1.

Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.

Recovered Data

Less than 10 errors in 10

12

bits transferred (OEM default settings)

Unrecovered Data

Less than 1 sector in 10

16

bits transferred

Miscorrected Data

Less than 1 sector in 10

21

bits transferred

Interface error rate:

Less than 1 error in 10

12

bits transferred

MTBF

1,400,000 hours

Preventive maintenance:

None required

This manual is related to the following products: