Fujitsu MHA2032AT, MHA2021AT manual Hap, Dap

Operations

1)At receiving the sequential read command, the disk drive sets the DAP and HAP to the start address of the segment and reads the requested data from the load of the segment.

HAP

Mis-hit data Empty area

DAP

2)The disk drive transfers the requested data that is already read to the host system with reading the requested data.

HAP

Requested data

Mis-hit data Empty area

DAP

3)After completion of the reading and transferring the requested data to the host system, the disk drive performs the read-ahead operation continuously.

HAP (Completion of transferring requested data)

Requested data

Read-ahead data

Empty area

DAP

4)The disk drive performs the read-ahead operation for all area of segment with overwriting the requested data. Finally, the cache data in the buffer is as follows.

HAP

Read-ahead data

DAP

Last LBA Start LBA

6-18 C141-E042-01EN