Experiments to see the advantages of using Web Workers to Render React Virtual DOM
JavaScript HTML
Clone or download
Latest commit 8fc5c01 Jan 11, 2017

README.md

React Renderer using Web Workers

A React Custom renderer using Web Workers. All the Virtual DOM reconcilliations happen in a WebWorker thread. Only node updates are sent over to the UI thread, result in a much more responsive UI.

An existing React application can leverage WebWorkers using this library with minimal change. Look at the usage section for details.

Demo

The demo is hosted at http://web-perf.github.io/react-worker-dom/. To run a local version of the demo,

  • Clone the repo run npm install to install all dependencies.
  • Build the app using npm run demo
  • Open http://localhost:8080/test/dbmonster/ to view the demo app, or http://localhost:8080/test/todo for the todo app.
  • Tweak the params in the URL to change to use web workers, increase number of components, etc.

Usage

A typical React application

A typical React application would looks something like the following.

// File: main.jsx
import React from 'react';
import reactDOM from 'react-dom';
reactDOM.render(<Component/>, document.getElementById('container'));

Using it with Web Workers

To use this renderer, we would need to split the above file into 2 parts, one that is on the page, and another that starts as a web worker.

// File: main.js - included using a script tag in index.html
import React from 'react';
import reactDOM from 'react-worker-dom'; // Instead of using react-dom
reactDOM.render(new Worker('worker.js'), document.getElementById('container'));

The worker.js file is the one that now holds the actual Component.

// File: worker.jsx - loaded in index.html using new Worker('worker.jsx') in the file script above; 
import React from 'react';
import ReactWorkerDOM from 'react-worker-dom-worker';
ReactWorkerDOM.render(<Component/>);

Look at test\dbmonster and test\todoapp directory for the examples.

Testing Performance

To manually look at frame rates, load the dbmonster demo pages in Chrome, and view the frame meter in devtools.

To automatically collect frame rates and compare it with the normal version

  • Run npm run demo to start the server and host the web pages
  • Run npm run perf chrome worker to test frame rates for various rows in chrome in a Web Worker. Instead of chrome, you could use android, and instead of worker, you could use normal to test the other combinations.
  • The frame rates are available in _dbmonster.json file, for each row count.

Roadmap

Here are the things that need to be done next.

  • Add support for form elements like <input>, <select>, etc.
  • Support event utilities that enable things like autofocus, etc.
  • Enable preventDefault() semantics in events.