define Shortest-Job-First (SJF) Scheduling ?, Basic Computer Science

Assignment Help:

• It is also known as Shortest-Process-Next (SPN).
• Shortest-Job-First (SJF) is a non-preemptive order in which waiting job (or process) with the smallest predictable run-time-to-completion is run next. In other language, when CPU is available, it is allotted to the process that has smallest next CPU burst.
• The SJF scheduling is mainly suitable for batch jobs for which the run times are known in advance. Since the SJF scheduling algorithm gives the minimum average time for a given set of processes, it is almost certainly optimal.
• The SJF algorithm helps short jobs (or processors) at the cost of longer ones.
• The understandable problem with SJF scheme is that it requires precise acquaintance of how long a job or process will run, and this information is not generally available.
• In the production environment where the same jobs run frequently, it may be possible to provide reasonable estimate of run time, based on the past presentation of the process. But in the development environment users not often know how their program will execute.
• The best SJF algorithm can do is to rely on user approximation of run times.
• Like FCFS, SJF is non preemptive therefore, it is not helpful in timesharing environment in which reasonable answer time must be sure.

Related Discussions:- define Shortest-Job-First (SJF) Scheduling ?

Rooted tree, Ask qu The figure below shows a rooted tree, 756_Find the hei...

Ask qu The figure below shows a rooted tree, 756_Find the height.png 1.1. Find the height/level of the tree as shown above?estion #Minimum 100 words accepted#

Operating systems, Consider the state transition diagram of Figure 3.9b. Su...

Consider the state transition diagram of Figure 3.9b. Suppose that it is time for the OS to dispatch a process and that there are processes in both the Ready state and the Ready/Su

Learn, The technique to mix C and assembly language is to apply the "asm" d...

The technique to mix C and assembly language is to apply the "asm" directive. To access C-language variables from assembly language, you just use the C identifier that name is a me

What is an abstract data type, QUESTION (a) What is an abstract data ty...

QUESTION (a) What is an abstract data type? (b) Give two limitations of the array implementation of lists. (c) Give the major disadvantage of the dynamic implementation o

Data input , Data Input : There are several aspects of data input that nee...

Data Input : There are several aspects of data input that need careful consideration. We shall assume that in a laboratory environment you are mainly concerned with entering data

What is the benefit of Threads?, Following are some causes why we use threa...

Following are some causes why we use threads in designing operating systems. A process with several threads makes a great server for instance printer server. For the reason that t

Integers, what is the size of a void integer and what is it''s range

what is the size of a void integer and what is it''s range

C programming, input is n positive numbers and reverse it, out put gv the a...

input is n positive numbers and reverse it, out put gv the absolute difference and give the reverse(magic number),using function reverseinteger, and function generate magicnumber

Determine recursive c function computes, QUESTION (a) Give the two cond...

QUESTION (a) Give the two conditions required by a binary tree of depth d to be an almost complete binary tree. (b) Determine what the following recursive C function compute

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd