Multitasking Operating System Last Updated : 23 Jul, 2025 Comments Improve Suggest changes Like Article Like Report Multitasking in operating systems allows multiple tasks to run in an concurrent (or interleaved) manner, enhancing system performance. Multiprogramming ensures that the CPU (a very fast device) is used by other processes when one process becomes busy with IO (very slow compared to CPU). Multitasking further enhances multiprograamming by allocating fixed slot to each process ready to execute. It mainly runs processes in round robin manner. We mainly try to make the best utilization of our main resource which is CPU (by allowing processes to run in an interleaved manner (one process gets CPU for a partial time and then other process gets CPU). Apart from CPU utilization, it also improves user experience as the system becomes more responsive and interactive, hence allows user to do multiple tasks. Multitasking Operating SystemTypes of Multi-Tasking Operating System1. Preemptive Multitasking Operating System In preemptive multitasking, the operating system can interrupt a running process and allocate the CPU to another process.The operating system decides how long a process should run before switching to another process.Preemption ensures that no single process monopolizes the CPU, improving system responsiveness.Examples include Windows 95, WindowsNT, Linux and UNIX-based operating systems.Advantages:Efficient CPU utilization by running multiple tasks concurrently.Better system responsiveness and user experience.Allows higher-priority processes to take precedence over lower-priority ones.Disadvantages:Context switching overhead, which can reduce performance.Complexity in process synchronization and management.Can lead to starvation if lower-priority processes are never allocated CPU time.2. Cooperative/Non-Preemptive Multitasking Operating SystemIn non-preemptive multitasking, also known as cooperative multitasking, the OS does not initiate context switching from one process to another.A context switch occurs only when processes voluntarily yield control or are logically blocked.Processes cooperate to allow multiple applications to run simultaneously, ensuring the system operates smoothly.Examples include older versions of Macintosh OS (8.0-9.2.2) and Windows 3.x.Advantages:Simpler to implement compared to preemptive multitasking.Lower overhead from context switching.Processes have more control over their execution.Disadvantages:Less efficient CPU utilization due to lack of automatic task switching.Risk of system unresponsiveness if a process fails to yield control.Difficult to manage real-time task priorities.For more details you can refer Difference between Preemptive and Cooperative Multitasking article.Components of Multi-Tasking Operating SystemTime Sharing: In this, many processes are allocated with resources of computer in respective time slots, processors time is shared with multiple processes.Context Switching: Context switching is a process of saving the context of one process and loading the context of another process. In simpler terms it is loading another process when the prior process has finished its execution.Multi-Threading: Multithreading is the ability of a program or an operating system to enable more than one user at a time without requiring multiple copies of the program running on the computer.Hardware Interrupt: When a process or an event requires urgent attention, hardware or software will signal with an interrupt. It informs the processor that a high-priority task has arisen that necessitates interrupting the running process.Process Scheduling: It is the operating system mechanism that allocates CPU time to processes based on scheduling algorithms.Process Synchronization: ensures coordinated access to shared resources, preventing conflicts between processes.Pros of Multi-Tasking Operating SystemMulti-Tasking Operating System is capable of executing multiple application simultaneously without slowing down the system.Each process is assigned specific length of time(i.e time sharing), hence a process does not have to wait for longer duration to utilize CPU. Starvation of process is not found in these operating system.A multitasking OS can effectively manage I/O devices, RAM, hard disks, CPUs and other computer resources.In Multi-Tasking Operating a user is capable of executing multiple programs at the same time, such as games, browser, MS Word and other services.Memory management is well-defined in multitasking operating systems. Because of this, the operating system does not grant any permission for unwanted apps to waste RAM.Cons of Multi-Tasking Operating SystemAs a single processor is executing multiple processes at the same time then there will be load on CPU and CPU may gets heat up.Computer system will be lagging if the processor is slow in Multi-Tasking Operating System while executing multiple programs simultaneously. Main memory(RAM) have to store multiple processes during multi tasking so there can be memory boundation if the main memory is overloaded. Comment More infoAdvertise with us D darkknight006 Follow Improve Article Tags : Operating Systems OS Basics Similar Reads Operating System Tutorial An Operating System(OS) is a software that manages and handles hardware and software resources of a computing device. Responsible for managing and controlling all the activities and sharing of computer resources among different running applications.A low-level Software that includes all the basic fu 4 min read OS BasicsWhat is an Operating System?An Operating System is a System software that manages all the resources of the computing device. Acts as an interface between the software and different parts of the computer or the computer hardware. Manages the overall resources and operations of the computer. Controls and monitors the execution o 5 min read Types of Operating SystemsAn operating system (OS) is software that manages computer hardware and software resources. 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This problem can be s 7 min read Compaction in Operating SystemCompaction is a technique to collect all the free memory present in the form of fragments into one large chunk of free memory, which can be used to run other processes. It does that by moving all the processes towards one end of the memory and all the available free space towards the other end of th 3 min read Belady's Anomaly in Page Replacement AlgorithmsBelady's Anomaly is a phenomenon in operating systems where increasing the number of page frames in memory leads to an increase in the number of page faults for certain page replacement algorithms. Normally, as more page frames are available, the operating system has more flexibility to keep the nec 11 min read Techniques to handle ThrashingPrerequisite - Virtual Memory Thrashing is a condition or a situation when the system is spending a major portion of its time servicing the page faults, but the actual processing done is very negligible. 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Different 13 min read PracticeLast Minute Notes – Operating SystemsAn Operating System (OS) is a system software that manages computer hardware, software resources, and provides common services for computer programs. It acts as an interface between the user and the computer hardware.Table of Content Types of Operating System (OS): ThreadsProcessCPU Scheduling Algor 15+ min read Operating System Interview QuestionsAn operating system acts as a GUI between the user and the computer system. In other words, an OS acts as an intermediary between the user and the computer hardware, managing resources such as memory, processing power, and input/output operations. Here some examples of popular operating systems incl 15+ min read Operating Systems - GATE CSE Previous Year QuestionsThe Operating System(OS) subject has high importance in GATE CSE exam because:large number of questions nearly 10-12% of the total asked significant weightage (9-11 marks) across multiple years which can also be seen in the below given table:YearApprox. Marks from OSNumber of QuestionsDifficulty Lev 2 min read Like