IBM IC35L020 Hard Drive Specifications - Page 33

Data integrity, Data loss at Power off, Write cache, Equipment status

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6.0 Data integrity 6.1 Data loss at Power off O The drive retains recorded information under all non-write operations. O No more than one sector can be lost by power down during write operation while write cache is dis- abled. O Power off during write operations may make an incomplete sector which will report hard data error when read. The sector can be recovered by a rewrite operation. O Hard reset does not cause any data loss. O If the write cache option is active, the data in the write cache will be lost. To prevent the loss of customer data, it is recommended that the last write access before power off be issued after setting write cache to off. 6.2 Write cache O Power off while write cache is enabled may cause the loss of data remaining in the cache that has not been flushed onto the disk media. Therefore, it is possible for data to be lost due to a power off after write command completion. O There are two ways to check if all data in the write cache has been flushed onto the disk. Checking just before power off is recommended to prevent data loss. - Confirm successful completion of Software Reset - Confirm successful completion of Flush Cache command 6.3 Equipment status Equipment status is available to the host system any time the drive is not ready to read, write, or seek. This status normally exists at power-on time and will be maintained until the following conditions are satisfied: O Access recalibration/tuning is complete O Spindle speed meets requirements for reliable operation O Self-check of drive is complete Appropriate error status is made available to the host system if any of the following conditions occur after the drive has become ready: O Spindle speed outside requirements for reliable operation O Occurrence of a WRITE FAULT condition Deskstar 60 GXP Hard disk drive specification 19

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6.0
Data integrity
6.1
Data loss at Power off
The drive retains recorded information under all non-write operations.
No more than one sector can be lost by power down during write operation while write cache is dis-
abled.
Power off during write operations may make an incomplete sector which will report hard data error
when read.
The sector can be recovered by a rewrite operation.
Hard reset does not cause any data loss.
If the write cache option is active, the data in the write cache will be lost.
To prevent the loss of
customer data, it is recommended that the last write access before power off be issued after setting
write cache to off.
6.2
Write cache
Power off while write cache is enabled may cause the loss of data remaining in the cache that has
not been flushed onto the disk media.
Therefore, it is possible for data to be lost due to a power off
after write command completion.
There are two ways to check if all data in the write cache has been flushed onto the disk. Checking
just before power off is recommended to prevent data loss.
-
Confirm successful completion of Software Reset
-
Confirm successful completion of Flush Cache command
6.3
Equipment status
Equipment status is available to the host system any time the drive is not ready to read, write, or seek.
This status normally exists at power-on time and will be maintained until the following conditions are
satisfied:
Access recalibration/tuning is complete
Spindle speed meets requirements for reliable operation
Self-check of drive is complete
Appropriate error status is made available to the host system if any of the following conditions occur after
the drive has become ready:
Spindle speed outside requirements for reliable operation
Occurrence of a WRITE FAULT condition
Deskstar
60 GXP Hard disk drive specification
19