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Multitasking System

 Multitasking system

·         Technically , multitasking is same as multi programming

·         In a multitasking operating system, s single user can execute multiple programs at the same time

·         We can also say, multitasking is the system capability to work on more than one job or process at the same time.

·         It means that whenever a job needs to perform I/O operation, the cpu can be used for execting some other job

 


                                                     diagram of multi tasking

 

 

·         There are two type of multitasking :

1.       Cooperative multitasking

2.       Preemptive multitasking

 

·         Co operative multitasking  in cooperative multitasking , program can aquire the cpu for the required amount of time a program canshare CPU with any other program that is executing simultaneously, if it does not currently require the CPU.

 

·         Preemptive multitasking. In preemptive multitasking the operating system allocates particularly time to a program . the CPU is preempted if a higher priority job arrives in a system. 

single user operating system  

2.      Multi user operating system 

3.       Batch processing operating system

4.      Multi programming operating system 

5.     Multi tasking operating system 

6.       Multiprocessing operating system

7.       Time sharing operating system

8.     Real time system    

 Comparison between multi tasking and multi programming

 

 

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