Developers love building all sorts of React apps because of its ability to process UI components in browsers to update them without unnecessary navigation. But that comes at a cost. React app’s size can be pretty large for most web applications, which causes a toll on performance. The reason for that is, React is a front-end library that doesn’t improve the website or application performance on its own; it has to be correctly configured and optimized on different aspects. Also, if you plan to attract lots of users to your website, you need to optimize the performance in high traffic conditions to avoid unnecessary hiccups.

For these reasons, knowing how to use best practices and ways to optimize web applications becomes essential for you as a developer or product manager for ensuring that your React app delivers a consistent and better user experience rather than a lagging one. In this blog, you will learn how to improve React app performance, especially in high traffic scenarios.


Tips to Improve React App Performance



For components that use primitive data, you can use React.PureComponents base class, which internally uses the implementation of shouldComponentUpdate() function to reduce the rendering time. This small yet smart practice can improve your component loading time to a great extent.


Immutable Data Structures

Avoid modifying objects directly by making object copies with desired data changes. Use immutable data structures that will automatically apply this process when there is any change in the object state. This will make the state change detection easy, which in turn improves the overall performance of your React app.


Production Build

To give code warnings and other useful insights about code, React has node environment checks spread all over the files. While this helps developers, it does not make any sense to pass it through when you deploy your app in the production environment. To remove these unnecessary code lines, make a production build using npm run build as a best practice, and improve your React app’s performance.


Compression (Gzip or Brotli)

To load your client-side JavaScript load faster, compress your JavaScript code using Gzip or Brotli on your application server. This will make fetching and serving faster, resulting in faster load time and components rendering.


React Developer Tools

It is available as an extension for Chrome, Firefox and helps you identify unnecessary rending of your react components by highlighting them with different colors. You can install it and open it while working on your react app. In the “Highlight Updates” box, you should see your react components marked with green, blue, yellow, or red. With red being the highest frequent updates, these colors indicate the possibility of unwanted and frequent rendering. This way, you can click on any element/component and inspect if it needs optimization based on the indicative color for the rendering cycle.


Chrome DevTools

Chrome development tools are offered by Google that runs in your chrome browser to edit and visualize changes in your web pages easily. These tools can help you analyze run-time performance issues in your react app without the need to make a build. Using Chrome DevTools, you can see loading components and their load time to identify potential bottlenecks and unnecessary rendering to optimize your code.


Improving React App Performance using LoadView

To begin with, LoadView is a cloud-based load testing tool that simulates virtual users on your website to check the performance on different matrices. It is a browser-based performance testing tool, perfect for modern JavaScript applications like React apps to accurately detect rendering issues & other bottlenecks. Virtual users in LoadView are generated using 40+ real browsers and devices to match real-world user behavior, which helps fine-tune your website for the best end-user experience. LoadView generates user load from multiple-geographical locations that further add value to your test scenarios to analyze location-specific behaviors and performance.

As React apps heavily depend on the browser actions, LoadView offers a powerful EveryStep Web Recorder that can simulate complex user behavior and paths to help you analyze react components rendering. With EveryStep Web Recorder, you can easily capture complex user interactions such as selection, mouse click event, mouse up/down event, movements, keypress/up/down event, hover, human verification checks, sorting, filtering, and more to see how your components render on these events.

As a developer, you can closely monitor components loading frequency and rendering time using LoadView and identify the problems before they impact your users in the production.

That’s not all. When a high number of users visit your website during a time window, your website performance can degrade, and your servers can go down, causing your users great trouble and damage your brand reputation. If your website is not performing well when high traffic comes, you can also suffer a great revenue loss during promotional events.

You can perform comprehensive load testing for your React application to check how your server and website resources are utilized in peak traffic conditions to identify performance bottlenecks and remove them proactively. This is especially important when you have an e-commerce website or a news website using React.


Conclusion: Tips to Improving React App Performance

Modern applications heavily use JavaScript and rely on browsers to provide a real-time experience and smooth browsing. React is one of the most popular JavaScript frameworks to build faster applications with great designs. However, React applications can quickly grow large in size, causing performance issues and glitches. Also, like any other application, high traffic can significantly impact the user experience. Using best practices and tools for coding and deployment, you can optimize your code to improve the React application’s performance.

LoadView is a cloud-based tool made for modern applications to optimize them for performance. LoadView offers many features that you can utilize for identifying potential bottlenecks and performance issues using detailed testing reports generated after testing. These reports contain details about resource utilization and performance metrics to help you quickly optimize your React app to enhance load time and performance under peak traffic conditions.

Sign up for LoadView and run up to 5 free load tests!