Fujitsu MHA2021AT, MHA2032AT manual Following shows the cache enabled data for next read command

Models: MHA2032AT MHA2021AT

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6.5 Read-Ahead Cache

2)Transfers the requested data that already read to the host system with reading the requested data from the disk media.

HAP

Stores the read-requested data upto this point

Read-requested data

Empty area

DAP

3)After reading the requested data and transferring the requested data to the host system had been completed, the disk drive stops command execution without performing the read-ahead operation.

HAP (stopped)

Read-requested data

Empty area

(stopped)

DAP

4) Following shows the cache enabled data for next read command.

 

Cache enabled data

 

Empty area

 

 

 

 

Start LBA

Last LBA

(2) Sequential read

When the disk drive receives the read command that targets the sequential address to the previous read command, the disk drive starts the read-ahead operation.

a.Sequential command just after non-sequential command

When the previously executed read command is an non-sequential command and the last sector address of the previous read command is sequential to the lead sector address of the received read command, the disk drive assumes the received command is a sequential command and performs the read-ahead operation after reading the requested data.

C141-E042-01EN

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Fujitsu MHA2021AT, MHA2032AT manual Following shows the cache enabled data for next read command