Disk Scheduling: Difference between revisions

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[[File:Disk Scheduling - Time.png|1000px]]
[[File:Disk Scheduling - Time.png|1000px]]
== Space Complexity Graph ==
[[File:Disk Scheduling - Space.png|1000px]]
== Time-Space Tradeoff ==
[[File:Disk Scheduling - Pareto Frontier.png|1000px]]

Latest revision as of 09:09, 28 April 2023

Description

When disk requests arrive at the disk device, they are queued for service and a disk scheduling algorithm is used to decide which of a waiting queue of disk requests to serve next.

Parameters

$n$: number of requests

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
FCFS 1979 $O(n)$ $O({1})$ Exact Deterministic
SSTF 1979 $O(n \log n)$ with binary tree $O(n)$ Exact Deterministic Space
SCAN 1979 $O(n \log n)$ $O(n)$ Exact Deterministic Space
LOOK 1979 $O(n \log n)$ $O(n)$ Exact Deterministic
C-SCAN 1979 $O(n \log n)$ $O(n)$ Exact Deterministic
C-LOOK 1979 $O(n \log n)$ $O(n)$ Exact Deterministic

Time Complexity Graph

Disk Scheduling - Time.png