Multiprocessing vs. Multitasking — What's the Difference?

Multiprocessing leverages the power of more than one CPU or multiple core processors to perform several tasks or parts of a task concurrently. This approach significantly boosts computational speed and efficiency, especially for complex or resource-intensive processes. In contrast, multitasking enables an operating system (OS) to handle multiple tasks by swiftly switching between them, so users experience the tasks as being performed simultaneously. While multiprocessing is a hardware-based strategy to increase performance, multitasking is a software-based approach to optimize the utilization of the CPU.

In multiprocessing systems, tasks are divided and processed in parallel, reducing the time required for processes to complete. This is particularly advantageous for applications that can be broken down into smaller, independent tasks. Meanwhile, multitasking involves the operating system's scheduler dividing CPU time among multiple tasks, which can include both user applications and system processes. The goal of multitasking is to ensure that the computer system is responsive to user input and that tasks are completed in an efficient manner, without wasting CPU cycles.

Multiprocessing systems require specially designed software that can effectively split tasks into parallel operations to be executed by the CPUs or cores. This necessitates a certain level of complexity in software design to manage data consistency and task synchronization. On the other hand, multitasking systems rely on the OS's capability to manage and allocate resources efficiently among the tasks, requiring sophisticated scheduling algorithms to minimize wait time and maximize CPU utilization.

An important distinction between the two concepts is their scalability. Multiprocessing can scale the computing power by adding more CPUs or cores, directly impacting the system's capability to handle more tasks simultaneously. In multitasking, the scalability is more about the efficiency of the OS in handling a larger number of tasks within the constraints of the existing hardware, particularly the single CPU's or core's processing capacity.

Both multiprocessing and multitasking are fundamental to modern computing, offering different but complementary strategies for enhancing system performance and user experience. Multiprocessing addresses the need for increased computational power through hardware, while multitasking focuses on optimizing the use of available hardware resources through intelligent software management.