Fujitsu MAP3147, MAP3367, MAS3735, MAP3735, MAS3367 specifications Write Cache

Models: MAP3735 MAP3147 MAS3367 MAP3367 MAS3735

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2.3 Write Cache

2.3Write 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-E167

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Fujitsu MAP3147, MAP3367, MAS3735, MAP3735, MAS3367 specifications Write Cache