A system has 12 tape drives. At time t0, p0 has maximum need 10 and holds 5, p1 needs 4 and holds 2, p2 needs 9 and holds 2. The system is in a safe state. Which is a safe sequence?
Pick an option to check yourself, or open the answer below.
Show answer & explanation
Correct answer: B. <p1, p0, p2>
Explanation
Free = 12 − 9 = 3. p1 needs 2 more: runs, frees 4 → 5. p0 needs 5: runs, frees 10. p2 needs 7: runs. So <p1, p0, p2>.
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