The first step to optimising your webpack build speed, is to know where to focus your attention.
This plugin measures your webpack build speed, giving an output like this:
npm install --save-dev speed-measure-webpack-plugin
or
yarn add -D speed-measure-webpack-plugin
SMP follows semver. If upgrading a major version, you can consult the migration guide.
SMP requires at least Node v6.
Change your webpack config from
const webpackConfig = {
plugins: [
new MyPlugin(),
new MyOtherPlugin()
]
}
to
const SpeedMeasurePlugin = require("speed-measure-webpack-plugin");
const smp = new SpeedMeasurePlugin();
const webpackConfig = smp.wrap({
plugins: [
new MyPlugin(),
new MyOtherPlugin()
]
});
and you're done! SMP will now be printing timing output to the console by default.
Check out the examples folder for some more examples.
Options are (optionally) passed in to the constructor
const smp = new SpeedMeasurePlugin(options);
Type: Boolean
Default: false
If truthy, this plugin does nothing at all. It is recommended to set this with something similar to { disable: !process.env.MEASURE }
to allow opt-in measurements with a MEASURE=true npm run build
Type: String|Function
Default: "human"
Determines in what format this plugin prints its measurements
"json"
- produces a JSON blob"human"
- produces a human readable output"humanVerbose"
- produces a more verbose version of the human readable output- If a function, it will call the function with the JSON blob being the first parameter, and just the response of the function as the output
Type: String|Function
Default: console.log
- If a string, it specifies the path to a file to output to.
- If a function, it will call the function with the output as the first parameter
Type: Object
Default: {}
By default, SMP derives plugin names through plugin.constructor.name
. For some
plugins this doesn't work (or you may want to override this default). This option
takes an object of pluginName: PluginConstructor
, e.g.
const uglify = new UglifyJSPlugin();
const smp = new SpeedMeasurePlugin({
pluginNames: {
customUglifyName: uglify
}
});
const webpackConfig = smp.wrap({
plugins: [
uglify
]
});
Type: Boolean
Default: false
If truthy, this plugin will attempt to break down the loader timing data to give per-loader timing information.
Points of note that the following loaders will have inaccurate results in this mode:
- loaders using separate processes (e.g.
thread-loader
) - these make it difficult to get timing information on the subsequent loaders, as they're not attached to the main thread - loaders emitting file output (e.g.
file-loader
) - the time taken in outputting the actual file is not included in the running time of the loader
These are restrictions from technical limitations - ideally we would find solutions to these problems before removing the (experimental) flag on this options