Difference between Look and C-Look Disk Scheduling AlgorithmIn this article, you will learn about the difference between the LOOK and C-LOOK Disk Scheduling Algorithm. But before discussing the differences, you have to know about the LOOK and C-LOOK Disk Scheduling Algorithm. What is the LOOK Disk Scheduling Algorithm?It is the more advanced version of the SCAN disk scheduling algorithm. In this algorithm, the head begins at one end of the disk and works its way to the other end, and serving all requests along the way. When the head reaches the end of one end's last request, it changes direction and returns to the first request, servicing all requests in between. Unlike SCAN, instead of going to the last track, this head goes to the last request and then changes direction. Example: Let's take an example to understand the LOOK Disk Scheduling Algorithm. Let's take a disk with 180 tracks (0-179) and the disk queue having input/output requests in the following order: 75, 90, 40, 135, 50, 170, 65, 10. The initial head position of the Read/Write head is 45 and would move on the right-hand side. Find the total number of track movements of the Read/Write head using the LOOK disk scheduling algorithm. Solution: Total head movements, The initial head point is 45, = (50-45) + (65-50) + (75-65) + (90-75) + (135-90) + (170-135) + (170-40) + (40-10) = 5 + 15 + 10 + 15 + 45 + 35 + 130 + 30 = 285 Advantages and Disadvantages of LOOK Disk Scheduling AlgorithmThere are various advantages and disadvantages of the LOOK Disk Scheduling Algorithm. These advantages and disadvantages are as follows: Advantages
Disadvantages
C-LOOK Disk Scheduling AlgorithmIt is a combination of the LOOK and SCAN disk scheduling algorithms. In this disk scheduling algorithm, the head begins from the initial request to the last request in the other direction and serves all requests in between. The head jumps in the other direction after finishing the last request at one end and proceeds towards the remaining requests, completing them in the same direction as previously. Unlike LOOK, it only responds to requests in one direction. Example: Let's take an example to understand the C-LOOK Disk Scheduling Algorithm. Let's take a disk with 180 tracks (0-179) and the disk queue having input/output requests in the following order: 75, 90, 40, 135, 50, 170, 65, 10. The initial head position of the Read/Write head is 45 and would move on the right-hand side. Find the total number of track movements of the Read/Write head using the C-LOOK disk scheduling algorithm. Solution: Total head movements, The initial head point is 45, = (50-45) + (65-50) + (75-65) + (90-75) + (135-90) + (170-135) + (170-10) + (40-10) = 5 + 15 + 10 + 15 + 45 + 35 + 160 + 30 = 315 Advantages and Disadvantages of C-LOOK Disk Scheduling AlgorithmThere are various advantages and disadvantages of the C-LOOK Disk Scheduling Algorithm. These advantages and disadvantages are as follows: Advantages
Disadvantages
Main Differences between the LOOK and C-LOOK Disk Scheduling AlgorithmHere, you will learn the main differences between the LOOK and C-LOOK Disk Scheduling Algorithm. The main differences between the LOOK and C-LOOK Disk Scheduling Algorithm are as follows:
Head-to-head Comparison between the LOOK and C-LOOK Disk Scheduling AlgorithmHere, you will learn the head-to-head comparison between the LOOK and C-LOOK Disk Scheduling Algorithm. The main differences between the LOOK and the C-LOOK Disk Scheduling Algorithm are as follows:
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