Seagate Cheetah ST3146854, User Manual

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Cheetah 15K.4 SCSI Product Manual, Rev. D 17
5.0 Reliability specifications
The following reliability specifications assume correct host/drive operational interface, including all interface
timings, power supply voltages, environmental requirements and drive mounting constraints (see Section 8.4).
Note.
[1] Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.
5.1 Error rates
The error rates stated in this specification 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
Recovereable 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
15
bits trans-
ferred. Unrecoverable Data Errors resulting from the same cause are treated as 1 error for that block.
Seek Errors
Less than 10 in 10
8
seeks
Read Error Rates [1]
Recovered Data Less than 10 errors in 10
12
bits transferred (OEM default settings)
Unrecovered Data Less than 1 sector in 10
15
bits transferred (OEM default settings)
Miscorrected Data Less than 1 sector in 10
21
bits transferred
MTBF 1,400,000 hours
Service Life 5 years
Preventive Maintenance None required