To access data in a hard disk, it requires the time to move the head to A. TASK: the desired track (seek time). Once the head has reached the correct track, we must wait for the desired sector to rotate under the read/write head (rotational latency). The last component of a disk access is the time to transfer a block of bits (transfer time). Your task is to: (1) find out the average seek time, rotational latency, transfer time and controller delay in the given factors: 512B sector, 5400 RPM, 3 ms average seek time, 100 MB/s transfer rate, O.2 ms controller overhead, idle disk. (2) What is the average read time in the given factors. (hint: Average read time = seek time + rotational latency + transfer time + controller delay)

To access data in a hard disk, it requires the time to move the head to A. TASK: the desired track (seek time). Once the head has reached the correct track, we must wait for the desired sector to rotate under the read/write head (rotational latency). The last component of a disk access is the time to transfer a block of bits (transfer time). Your task is to: (1) find out the average seek time, rotational latency, transfer time and controller delay in the given factors: 512B sector, 5400 RPM, 3 ms average seek time, 100 MB/s transfer rate, O.2 ms controller overhead, idle disk. (2) What is the average read time in the given factors. (hint: Average read time = seek time + rotational latency + transfer time + controller delay)

Operations Research : Applications and Algorithms

4th Edition

ISBN:9780534380588

Author:Wayne L. Winston

Publisher:Wayne L. Winston

Chapter20: Queuing Theory

Section20.10: Exponential Queues In Series And Open Queuing Networks

Problem 11P

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