1)In the case that the contents of the data buffer is as follows for example and the previous command is a sequential read command, the disk drive sets the HAP to the address of which the hit data is stored.
Last position at previous read command
HAP | HAP (set to hit position for data transfer) |
Cache data | Full hit data |
Cache data
DAP
Last position at previous read command
2) The disk drive transfers the requested data but does not perform the
HAP (stopped)
Cache data | Full hit data | Cache data |
3)The cache data for next read command is as follows.
Cache data
Start LBA | Last LBA |
(4)Partially hit
A part of requested data including a lead sector are stored in the data buffer. The disk drive starts the data transfer from the address of the hit data corresponding to the lead sector of the requested data, and reads remaining requested data from the disk media directly. The disk drive does not perform the
Following is an example of partially hit to the cache data.
Cache data
Start LBA | Last LBA |
6 - 20 |