explain CPU scheduling and its objectives?, Basic Computer Science

Definition of CPU scheduling:
The assignment of physical processors to processes allows processors to complete work. The process of determining that for which process which processor should be assign this process is called processor scheduling or CPU scheduling.
When one or more than one process is run able, the operating system must choose which one first. The division of the operating system concerned with this decision is called the scheduler, and algorithm it uses is called the scheduling algorithm.

Objectives of scheduling (objectives)
Many objectives must be regarded as in the design of a scheduling discipline. In exacting, a scheduler should consider fairness, efficiency, reaction time, turnaround time, throughput, etc., Some of these objectives depends on the system one is using for instance batch system, cooperative system or real-time system, etc. but there are also some objectives that are desirable in all systems.

General objectives
• Fairness is vital under all circumstances. A scheduler makes sure that each process gets its fair share of the CPU and no process can undergo indefinite postponement. Note that giving equivalent or equivalent time is not fair. Think of security control and payroll at a nuclear plant.
• The scheduler has to assure that system''s policy is enforced. For instance, if the local policy is safety then the safety control processes must be talented to run whenever they want to, even if it means delay in payroll processes.

• Scheduler should remain the system (or in exacting CPU) demanding cent percent of the time when possible. If the CPU and all the Input / Output devices can be kept running all the time, more work obtains done per second than if some components are idle.
• A scheduler should reduce the time batch users must remain for an output.
• A scheduler should exploit the number of jobs processed per component time.
• A scheduler should reduce the response time for interactive user.


A little thought will show that some of these objectives are opposing. It can be shown that any scheduling algorithm that supports some class of jobs hurts another class of jobs.

Posted Date: 5/2/2012 7:45:13 AM | Location : United States







Related Discussions:- explain CPU scheduling and its objectives?, Assignment Help, Ask Question on explain CPU scheduling and its objectives?, Get Answer, Expert's Help, explain CPU scheduling and its objectives? Discussions

Write discussion on explain CPU scheduling and its objectives?
Your posts are moderated
Related Questions
Input/Output Services:   Every operating system, large or small, provides input/output services for each device in the system. The operating system includes I/O device driver

A utonomous Rational Agents: In many cases, it is not accurate to talk about a particular program or a particular  robot, as the combination of and software and hardware in so

A string S is said to be "Super ASCII", if it contains the character frequency equal to their ascii values. String will contain only lower case alphabets (''''''''a''''''''-'''''''

The divisions which make a macro are: • Declaration of the macro Code of the macro Macro termination directive The assertion of the macro is done the following way: Name Macro [par

Our instructor gave us a project in making a mechanical game or simple device using assembly language, can anyone give me a an example of a project description for our proposal?

FUNDAMENTALS OF COMPUTERS 1. Describe the importance of video in multimedia. What are some of the tips to keep in mind while making video for the web? 2. Specify the steps t

A string S is said to be "Super ASCII", if it contains the character frequency equal to their ascii values. String will contain only lower case alphabets (''''''''a''''''''-'''''''

WHAT IS CAI ITS PITFALLS

create a flowchart showing average score for the 3 quizzes assume that there are 3 sections each having 5 students the only valid number to be entered is 1-100 for the quizzes shou

Padovan sequence