Question
Which of the following I/O scheduling algorithms
provides the most efficient disk access for systems with many requests clustered around a central location on the disk?ΒSolution
The LOOK algorithm is an optimized version of the SCAN algorithm. It moves the disk arm in one direction servicing requests, and when it reaches the end, it reverses direction, servicing requests in that direction. LOOK improves on SCAN by stopping the movement as soon as there are no requests in the current direction, thereby reducing unnecessary disk movement. This results in more efficient disk access, especially when requests are clustered near a central location. Option A (FCFS): FCFS is the simplest scheduling algorithm but not optimal for disk I/O since it can result in significant seek times as the disk arm moves back and forth across the disk. Option B (SSTF): While SSTF minimizes the seek time by always choosing the request closest to the current position, it can cause starvation for requests that are far from the current head position, and it's not ideal for clustered requests. Option C (SCAN): SCAN is less efficient than LOOK because it always scans to the end of the disk, even if there are no requests to be serviced in that direction. Option E (CLOOK): CLOOK is a variation of LOOK that moves in one direction and then jumps to the other side of the disk, but for clustered requests, LOOK is generally more efficient as it doesnβt require the disk to jump to the opposite end.
Select the correct combination of mathematical signs that can sequentially replace the β@β sign and balance the following equation.
16@5@4@2@...
Which among the given operators should replace the β%β (in the same order) in the given expression below:
9 % 14 % 9 % 90 % 42 % 15
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If '@' denotes 'addition', '#' denotes 'subtraction', '$' denotes 'multiplication' and '%' denotes 'division', then what will be the value of the follow...
If A denotes '+', B denotes ' X ', C denotes ' - ' and D denotes 'Γ·', then what will come in place of '?' in the following equation?
117 D 13 B ...
(19 % 3) * 11 = 2 and 9 * 3 % 2 = 5. Then, 8 % 4 * 2 = ?
By interchanging the given two signs and numbers which of the following equation will be correct?
Γ and +, 6 and 4
- Which two signs should be interchanged to correct the given equation?
5 + 3 Γ 8 β 12 Γ· 4 = 3 If '+' means 'subtraction', ' X ' means 'addition', '-' means 'division' and 'Γ·' means 'multiplication', then what is the value of the following expres...