Write Cache - Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications

2.3

Write Cache

The IDD is equipped with a write cache function in order to reduce the INIT's command processing time.
If that operation is permitted by the MODE SELECT command (caching parameters: Page code = 8,
WCE bit), at the point when the IDD completes the transfer of all data specified in the WRITE or
WRITE EXTENDED command, it reports the GOOD status and terminates the command.
Note:
If the write cache function is permitted, data transferred form the INIT by a WRITE or WRITE
EXTENDED command are written to the disk media after the GOOD status is reported, so when an
unrecoverable write error is detected in that write operation, sense data is generated. When those
sense data is being held, the IDD ordinarily responds to the command that is executed next by a
"CHECK" status (deferred error), notifying the INIT that sense data is being held. However,
ordinarily, it is troublesome for the INIT to retry when there is an unrecoverable error in a write
cache operation, so adequate caution should be exercised when using this function.
C141-C010
2.3 Write Cache
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