Fujitsu MHA2021AT Product Manual page 158

2) Transfers the requested data that already read to the host system with reading
the requested data from the disk media.
HAP
Read-requested data
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.
Read-requested data
4) Following shows the cache enabled data for next read command.
Cache enabled data
Start 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.
C141-E042-01EN
Stores the read-requested
data upto this point
DAP
HAP
DAP
Last LBA
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.
6.5 Read-Ahead Cache
Empty area
(stopped)
Empty area
(stopped)
Empty area
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