Datasheet

7.4 Error rates
Error rates fall into two categories:
y Recoverable errors
y Nonrecoverable errors
The following error rates assume that no attempts are made to read or write in areas already identified as
being defective. The error rates are defined for the drive operating at the full range of environmental con-
ditions and are shown in Section 7.1 “Environment” on page 21. The voltage limits are shown in
Section 7.2, “DC Power Requirements” on page 23.
7.4.1 Recoverable errors
A recoverable error is defined as an operation that failed the first time but succeeded in recovering the
error when the drive error recovery procedure was invoked. ECC On-The-Fly, which is always active, is
transparent to the system and is not counted as a recoverable error.
A typical drive shall have no more than one recoverable error per 100 million bits transferred (1 in 10
8
)
when operated at nominal voltage and environmental condition. The typical disk drive error rate
represents the geometric mean of the error rates of the total disk drive population. The size of the drive
population is 50 drives or more.
Each drive in the population shall have no more than one recoverable error per 10 million bits transferred
(1 in 10
7
) when operated at full range of voltage and environmental conditions and the operating vibration
levels stated in Section 7.6, “Vibration and Shock” on page 27.
7.4.2 Nonrecoverable errors
A nonrecoverable error is defined as an operation that failed and was not recovered by the fixed disk
error recovery procedure. No drive has more than one nonrecoverable error per 10 trillion bits transferred
(1 in 10
13
) when operated at the full range of voltage and environmental conditions.
Hard disk drive specification for DSCM-11000/-10512/-10340
24