Reliability Specifications; Error Rates; Recoverable Errors; Unrecoverable Errors - Seagate Constellation ST9500622SS Product Manual

6.0

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.
Seek error rate:
1
Read Error Rates
Recovered Data
Unrecovered Data
Miscorrected Data
Interface error rate:
Mean Time Between Failure (MTBF):
Annualized Failure Rate (AFR):
Preventive maintenance:
1. Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.
6.1

Error rates

The error rates stated in this manual assume the following:
• The drive is operated in accordance with this manual using DC power as defined in paragraph 7.3, "DC
power requirements."
• 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.
6.1.1

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.
6.1.2

Unrecoverable Errors

An unrecoverable data error is defined as a failure of the drive to recover data from the media. These errors
occur due to head/media or write problems. Unrecoverable data errors are only detected during read opera-
tions, but not caused by the read. If an unrecoverable data error is detected, a MEDIUM ERROR (03h) in the
Sense Key will be reported. Multiple unrecoverable data errors resulting from the same cause are treated as 1
error.
Constellation.2 SAS Product Manual, Rev. H
Less than 10 errors in 10
Less than 10 errors in 10
Less than 1 sector in 10
15
Less than 1 sector in 10
21
Less than 1 error in 10
12
1,400,000 hours
0.62%
None required
seeks
8
bits transferred (OEM default settings)
12
bits transferred
bits transferred
bits transferred
15