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Consider a magnetic disk drive with 8 surfaces, 512 tracks per surface, and 64 sectors per track. Sector size is 1 KB.The average seek time is 8 ms, the track-to-track access time is 1.5 ms, and the drive rotates at 3600 rpm. Successive tracks in a cylinder can be read without head movement.
Estimate the time required to transfer a 5-MB file.

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Cylinder capacity = 8*64*1 Kb = 512 kB

Seek time = 8ms

Rotational latency = 1/2*revolution time = 60/3600*2 = 8.3 ms

MB means we need 10 cylinder, so 9 times tack to track access time needed in order to access 10 cylinder. i.e. transfer time + 9*track to track access time 1 track transfer time = 8*60/3.6 ms = 133.33 ms

Total time = seek time + 10*(per Tack transfer time + Rotational latency) + 9*(track to track access time)

= 8 + 10*( 133.33 + 8.3) + 9*1.5 = 1425.5 ms

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