Cheetah 10K.6 FC Product Manual, Rev. B | 13 |
5.0Reliability 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 | Less than 10 errors in 108 seeks |
Read Error Rates1 |
|
Recovered Data | Less than 10 errors in 1012 bits transferred (OEM default settings) |
Unrecovered Data | Less than 1 sector in 1015 bits transferred |
Miscorrected Data | Less than 1 sector in 1021 bits transferred |
Interface error rate | Less than 1 error in 1012 bits transferred with minimum receive eye |
| Less than 1 error in 1014 bits transferred with typical receive eye |
| (see Section 9.6.4, "Differential PECL input." on page 61) |
MTBF | 1,200,000 hours |
Service life | 5 years |
Preventive maintenance | None required |
1.Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.
5.1Error 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 6.2, "DC power requirements."
•The drive has been formatted with the
•Errors caused by media defects or host system failures are excluded from error rate computations.
•Assume random data.
5.1.0.1Interface errors
An interface error is defined as a failure of the receiver on a port to recover the data as transmitted by the device port connected to the receiver. The error may be detected as a running disparity error, illegal code, loss of word sync, or CRC error. The total error rate for a loop of devices is the sum of the individual device error rates.
5.1.1Environmental interference
When evaluating systems operation under conditions of electromagnetic interference (EMI), the performance of the drive within the system is considered acceptable if the drive does not generate an unrecoverable condi- tion.
An unrecoverable error, or condition, is defined as one that:
•is not detected and corrected by the drive itself
•is not detected from the error or fault status provided through the drive or
•is not recovered by normal drive or system recovery procedures without operator intervention
5.1.2Write errors
Write errors can occur as a result of media defects, environmental interference, or equipment malfunction. Therefore, write errors are not predictable as a function of the number of bits passed.
If an unrecoverable write error occurs because of an equipment malfunction in the drive, the error is classified as a failure affecting MTBF. Unrecoverable write errors are those that cannot be corrected within two attempts at writing the record with a read verify after each attempt (excluding media defects).
5.1.3Seek 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 (15h) is reported with a Medium error (3h) or Hardware error (4h) reported in the