Compare load times of CJS and AMD module systems

npm install cjs-vs-amd-benchmark
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CJS/AMD load time benchmark

Compare load times of two module systems.

It's basic benchmark that compares speed of both systems when used in development mode.

Main point is to prove that on request server-side generation of a bundle is not necessarily slower than loading modules asynchronously from the browser. It's actually opposite and difference can be significant. See the results section for numbers.

AMD modules are loaded with RequireJS and CommonJS modules are bundled on request with Webmake.

There's no prebuild step, in both cases modules are loaded/bundled on request. In case of AMD, they're loaded asynchronously in a browser. In case of CJS when request occurs they're read from filesystem, bundled and served in one file.

To see fair results (adequate to your development environment) benchmark needs to be installed and launched locally.

You can also check it working at medyk.org:3700, but mind it's backed with basic Node.js server setup (not very efficient for AMD), and due to extra latency results you'll see, will be worse than when running same on your localhost.


Install package:

$ npm install cjs-vs-amd-benchmark

Generate dummy modules (by default it resembles 400 modules tree from existing real world project)

$ npm run setup

You can generate custom number of out of provided modules map:
See bin/default-deps-map.json on how it should be constructed.

$ bin/generate --mapPath=path/to/custom/map

Start server (defaults to port 3000)

$ npm start

If you prefer other port, do:

$ bin/start --port=8080

Load the benchmark on corresponding port, e.g. localhost:3000


Following load times were measured on 2008 MBP with local setups of Node.js and Nginx server.

Results show that in general AMD resolution is slower, but with well configured HTTP server it can match the speed of CJS resolution in some browsers (see Nginx and Chrome results for AMD).

Each number is average of 5 runs.

(basic setup on v.0.10.13)
Google Chrome
(basic setup on v.0.10.13)
Nginx (v1.0.10)
Google Chrome
Nginx (v1.0.10)
CommonJS (via Webmake) 299ms 273ms N/A N/A
AMD (via RequireJS) 896ms 548ms 280ms 487ms
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