Seagate ST600MP0084 - 4K ユーザーズマニュアル

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S
EAGATE 
E
NTERPRISE 
P
ERFORMANCE 
15K HDD 
AND 
E
NTERPRISE 
T
URBO 
SSHD SAS P
RODUCT 
M
ANUAL
, R
EV
. B
 
 12
  
5.0 Reliability specifications
The following reliability specifications assume correct host and drive operational interface, including all interface 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 in accordance with this manual using DC power as defined in paragraph 6.3, "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.
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 Error Correction when needed.
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
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 operations, 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 th e same 
cause are treated as 1 error.
5.1.3
Seek errors
A seek error is defined as a failure of the drive to position the heads to the addressed track. After detecting an initial seek  error, the drive 
automatically performs an error recovery process. If the error recovery process fails, a seek positioning error (Error code = 15h or 02h) will 
be reported with a Hardware error (04h) in  the Sense Key.   Recoverable seek errors are specified at Less than 10 errors in 10
8
 seeks. 
Unrecoverable seek errors (Sense Key = 04h) are classified as drive failures.
5.1.4
Interface errors
An interface error is defined as a failur e of the receiver on a port to recover the data as transmitted by the device port conn ected to the 
receiver. The error may be detected as a running disparity error, illegal code, loss of word sync, or CRC error. 
5.2
Reliability and service
Integrators can enhance the reliability of En terprise Performance 15K HDD and Enterprise Turbo SSHD disk drives by ensuring that the 
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 
Mean Time Between Failure (MTBF):
2,000,000 hours
Annualized Failure Rate (AFR)
0.44%
Preventive maintenance:
None required