Consider a system with 0 -199 track. Suppose there are seven requests: 18, 27,…
Consider a system with 0 -199 track. Suppose there are seven requests: 18, 27, 50, 85, 130, 150, and 195. The disk arm is supposed to travel using scan algorithm while the read/write arm is at 60 currently moving from lower index to higher index track. What is the total seek time?
Answer: 320 — Step 1: The disk arm starts at track 60 and moves upward (toward higher indices) as per the scan algorithm. Step 2: It travels from track 60 to the highest…
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Correct answer: 320
Step 1: The disk arm starts at track 60 and moves upward (toward higher indices) as per the scan algorithm.
Step 2: It travels from track 60 to the highest track (199), covering a distance of (199 - 60) = 139.
Step 3: After reaching track 199, the arm reverses direction and moves downward to serve the highest pending request below 199, which is track 18.
Step 4: The distance from track 199 to track 18 is (199 - 18) = 181.
Step 5: Total seek time = 139 + 181 = 320.
हिन्दी उत्तर: स्कैन एल्गोरिथ्म के अनुसार, डिस्क आर्म 60 से ऊपर की ओर जाता है, 199 पर पहुँचता है और फिर नीचे की ओर मुड़ता है। 199 से 18 तक की दूरी (199 - 18) = 181 है। कुल स्किम टाइम = (199 - 60) + (199 - 18) = 320।