MULTIPROCESSING: WHAT IT CONSISTS OF, TYPES, REQUIREMENTS, ADVANTAGES - TECHNOLOGY - 2025

The multiprocessing, applied to the computer, is a form of operation of a computer where it is physically more than one processor. The aim is to be willing to run different parts of a program at the same time.

These multiple central processing units (CPUs) are in close communication, sharing the bus, memory, and other peripheral devices of the computer. Since multiple processors are available, multiple processes can run at the same time.

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Multiprocessing refers more to the number of CPU units, rather than the number of processes running simultaneously. If the hardware provides more than one processor, then that is multiprocessing. It is the ability of the system to harness the computing power of multiple processors.

The multiprocessing system is very useful when you want to have a high enough speed to process a large set of data. These systems are mostly used in applications such as weather forecasting, satellite control, etc.

This type of multiprocessing system first appeared in large computers or mainframes, before reducing its cost to ensure its inclusion in personal computers.

What is multiprocessing?

With the support of a multiprocessing system, several processes can be executed in parallel.

Suppose that processes Pr1, Pr2, Pr3 and Pr4 are waiting to be executed. In a single processor system, one process will run first, then the next, then the other, and so on.

However, with multiprocessing, each process can be set to a particular CPU for processing.

If it is a dual-core processor, with two processors, two processes can be executed simultaneously and thus these will be twice as fast. Similarly, a quad-core processor will be four times faster than a single processor.

As a specific function is assigned to be performed by each processor, they will be able to execute their work, deliver the set of instructions to the next processor, and begin working on a new set of instructions.

For example, a larger processor could use "slave" processors to perform various cleaning tasks, such as memory management.

Similarly, different processors can be used to manage data communications, memory storage, or arithmetic functions.

Difference between multiprocessing and multiprogramming

A system is multiprocessing by having more than one processor physically, and it can be multiprogramming when it has multiple processes running simultaneously.

Therefore, the difference between multiprocessing and multiprocessing is that multiprocessing runs multiple processes at the same time on multiple processors, whereas multiprocessing keeps multiple programs in main memory and runs them simultaneously through a single CPU.

That is, multiprocessing occurs through parallel processing, while multiprogramming occurs when a single CPU switches from one process to another.

Requirements

In order to use the multiprocessing system effectively, the computer system must have the following:

Processor support

You must have a set of processors that have the ability to use them in a multiprocessing system.

Motherboard bracket

A motherboard capable of containing and handling multiple processors. This means additional sockets or slots for added chips.

Operating system support

The entire multiprocessing task is managed by the operating system, which assigns the different tasks to be performed by the various processors in the system.

Applications designed to be used in multiprocessing are said to be stitched, which means that they are divided into smaller routines that can be run independently.

This allows the operating system to allow these threads to run on more than one processor simultaneously, resulting in multiprocessing and better performance.

Types of multiprocessing

Symmetric multiprocessing

In this type of multiprocessing, all processors have a mutual relationship at the same level of equality, that is, there is no master-slave relationship between them.

All processors communicate with each other, since each contains a copy of the same operating system.

An example of the symmetric multiprocessing system is the Encore version of Unix for the Multimax computer.

Asymmetric multiprocessing

In this type of multiprocessing, there is a master processor that gives instructions to all the other processors, assigning each one a previously defined task. This is the most economical option, maintaining a master-slave relationship between the processors.

This type of multiprocessing only existed until symmetric multiprocessors were introduced.

Advantage

Higher productivity

With multiprocessing you will have more tasks completed in a much shorter amount of time.

If several processors work together then system performance increases by increasing the number of processes executed per unit of time.

Higher reliability

When a processor fails, multiprocessing turns out to be more reliable, because in this situation the system will slow down, but it will not crash. This ability to continue working despite failure is known as graceful degradation.

For example, if one processor fails out of a total of five, then the job will not fail, but the remaining four processors will share the work of the failed processor. Therefore, the system will run 20% slower, instead of completely crashing.

Saving money

These systems can generate long-term money savings over single-processor systems because the processors can share power supplies, peripheral devices, and other devices.

If there are multiple processes that share data it is better to program them in multiprocessing systems to share the data, rather than having different computer systems with multiple copies of that data.

Disadvantages

Higher purchase cost

Although multiprocessing systems are cheaper in the long run than using multiple computer systems, they are still quite expensive.

It is much cheaper to buy a simple system with a single processor than a multiprocessor system.

Complex operating system

A more complex operating system is required in multiprocessing systems.

This is because by having multiple processors that share memory, devices, etc. the distribution of resources to the processes is more complicated than if there were only one processor.

Large amount of memory is required

All processors in the multiprocessing system share main memory. Therefore, a much larger memory pool is required compared to single processor systems.

References

1. Dinesh Thakur (2019). Definition Multiprocessor Operating System. Ecomputer Notes Taken from: ecomputernotes.com.
2. Tutorials Point (2019). Difference between multitasking, multithreading and multiprocessing. Taken from: tutorialspoint.dev.
3. Encyclopaedia Britannica (2019). Multiprocessing. Taken from: britannica.com.
4. Techopedia (2019). Multiprocessor. Taken from: ceilingpedia.com.
5. Kristi Castro (2018). Multiprocessor Systems. Tutorials Point. Taken from: tutorialspoint.com.