Free Files and disks lessonsFiles and disks · Stage 1 · Disks · Step 2
Disk scheduling
Order a queue of requests to cut head movement: FCFS, SSTF, SCAN, C-SCAN and LOOK. About 15 minutes.
Which policy can leave a request waiting indefinitely if new requests keep arriving close to the head?
- ASSTF (shortest seek time first)
- BSCAN
- CFCFS
Show the answer
SSTF (shortest seek time first). A far-away request is always beaten by closer ones.
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