What Are Multi-process and Multithreading in NodeJS?

NodeJS is a moniker that is commonly mentioned when it comes to “popular technology.” Because of the widespread use of this technology, organisations such as NASA, Trello, Uber, Linked In, Netflix, eBay, and others are relying on it to power their strong applications.

Nodejs developers are employed by roughly 43 percent of businesses to create their apps, owing to the capabilities and flexibility of the language in terms of developing a high-performing application that can handle large amounts of data.

However, despite the fact that NodeJS is integrated with numerous strong capabilities, some of its “essential” elements are as follows:

Thread execution in a non-blocking manner



Build vs. Compile: What’s the difference?


Code execution in a synchronous fashion

Sockets and two-way data binding are two types of data binding.

NodeJS is a sturdily constructed framework. As a result, we will not cover all of its characteristics in this article; instead, we will concentrate on the fact that it is “multithreaded” in nature. To be quite honest, the multithreading capability of NodeJs is what most developers and businesses use to decide whether or not to include it in their tech stack.

As a result, let us learn everything we can about it in order to create more exact goals.

We need first understand a bit more about NodeJS as a technology before moving on to the next step:

What exactly is NodeJS?

NodeJS is a JavaScript-based runtime environment that is platform-independent and available to everyone for free. Because of this, the technology is single-threaded. It, on the other hand, makes advantage of numerous background threads to execute the code in an asynchronous manner.

Because of NodeJS’s non-blocking functionality, various callbacks are processed by other threads, which are initially assigned to the event loop, rather than the event loop itself. The NodeJS runtime does an outstanding job with this function.

The following is the aim of NodeJS:

JavaScript was created as a single-threaded programming language to act as the front-end of an application when it was first introduced by ultimate status bar. This indicates that only a single set of instructions might be executed at a given point in time, as opposed to many sets.

The execution would only go on to the next block after the current block had been completed successfully. This method was, on the other hand, significantly slower than the multithreaded approach, but it made JavaScript implementation simpler.

Although as time passed and customer expectations grew dramatically, JavaScript’s ability to adapt to changing market conditions and enhance itself became increasingly important.

As a result, with the introduction of NodeJS in 2009, JavaScript was elevated to the status of full-stack application development language, with NodeJS handling the back-end code.
Furthermore, when you employ node.js engineers, you will have access to a variety of NodeJS frameworks that will allow you to achieve multithreading functionality for your application.

The NodeJS development process is as follows:

NodeJS makes use of two different types of threads:

There are a lot of auxiliary threads in the worker pool.

The main thread is controlled by an event loop.

In the event loop, functions and callbacks are registered for future execution and are then executed. It works on the same thread of JavaScript code as the rest of the application. If the JS action causes the thread to become stuck, the vent loop will be automatically stopped.

In the worker pool, threads are created and managed; they synchronously do tasks and return to the event loop with the required result, which executes the callback that was supplied with the result.

In layman’s terms, the worker pool is in charge of managing the asynchronous I/O activities on the server (interactions with the system network and disk). The worker pool is largely utilised by modules such as crypto and fs.

Everything appears to be in order, except when it comes to the simultaneous execution of complicated activities.

Any function that takes a lengthy time to complete can cause the main thread to become stalled by daily tribute. However, the release of NodeJS version 10.5.0, which has multithreading capabilities, offered the right answer for the problem at hand.

Using the worker thread module, you may perform simple multithreading:

The amazing worker thread module was added in NodeJS v10.5.0, which was released in June of this year. In the JavaScript runtime environment, it allows for the implementation of concurrency to be achieved. With the assistance of this module, it is possible to create NodeJS apps that are completely functional and run in many threads. An entrepreneur must recruit nodejs developers that are capable of working with NodeJS versions 10.5.0 and above.

But even if you employ a resource to assist you with your application development, you must be familiar with its details in order to participate completely to the development.

According to technical definition, a worker thread is code that is launched on a separate thread. To begin using the worker thread, your developer would need to begin by importing the worker threads module into his or her project. In addition, they would have to construct an instance of the worker class in order to establish a worker thread of their own.

The following are the two most important considerations when developing a worker class:

In the first case, a path to the files with the.mjs or.js extensions would be provided, along with the worker thread codes.

A worker data property would be provided to the object by the second method, which would include the data of the worker thread at the moment of execution.
Worker threads have the capability of dispatching several message events at the same time. In reality, the callback technique is given the highest priority.

The communication mechanisms between the worker threads are event-based; as a result, listeners are prepared to be called once an event is transmitted by the worker thread to the rest of the programme.

Worker threads can be used in a variety of ways.

Worker threads can be used in two different ways by developers:

The first approach is as follows:

It is necessary for a NodeJS developer to create a worker thread, run the code in it, and then send the result back to the parent thread. Because of this method, every time a new job is created, it is essential to construct a new worker from the ground up.

The second approach is as follows:

The developer can use the event to launch a worker thread and configure listeners for it. Every time a message is pushed, the worker thread would run the code and return the results back to the parent thread. Meanwhile, the worker thread remains alive and ready to be used in the future.

The second approach is referred to as the labour pool. The technique first generates a pool of workers and places them on hold, only dispatching the message event to execute the job when it is necessary.

Multiprocessing in NodeJS is as follows:

It is possible to take advantage of the multi-core capabilities provided by NodeJS by running processes on the system by whiite list. One of the most well-known runtime environments includes a “cluster,” which is a module that supports multi-processing.

The module enables for the spawning of many child processes, each of which shares a common port. As a result, while these child processes are active, a NodeJS-based system is capable of handling a greater amount of demand.


With the worker threads module, it is simple to include multithreading into a NodeJS application. However, in order to get optimum integration and a simplified development process, you would need to employ node.js developers that would create a NodeS application that was highly optimised and performed quickly.

NodeJS will be more accessible to developers and company owners working in calculation-intensive sectors such as big data, artificial intelligence, and machine learning projects as a result of the support for multithreading.