|
|
|
|
|
|
|
|
|
|
|
|
|
|
• |
Read
and cache a whole track
|
|
|
|
• |
Automatic
in some controllers
|
|
|
|
• |
Subsequent
reads to same track have zero rotational
|
|
latency
– good for locality of reference!
|
|
|
|
• |
Disk
arm available to seek to another cylinder
|
|
|
• |
Start
from current head position
|
|
|
|
• |
Start
filling cache with first sector under head
|
|
|
|
• |
Signal
completion when desired sector is read
|
|
|
• |
Start
with requested sector
|
|
|
|
• |
When
no cache, or limited cache sizes
|
|