(3)Sequential read
When the disk drive receives the read command that targets the sequential address to the previous read command, the disk drive tries to fill the buffer space with the read ahead data.
a. Sequential command just after
1)At receiving the sequential read command, the disk drive sets the DAP and HAP to the sequential address of the last read command and reads the requested data.
HAP
| Empty data |
|
|
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 |
Empty data
DAP
3)After completion of the reading and transferring the requested data to the host system, the disk drive performs the
HAP
Requested data |
Read- ahead data
Empty
data
DAP
6 - 16 |
|