High CPU usage while running on OS X

Created by: dceddia

After running npm start, the node process consumes ~40% CPU on my machine:

I found that setting a polling interval in the the WebpackDevServer helped:

new WebpackDevServer(compiler, {
    historyApiFallback: true,
    hot: true, // Note: only CSS is currently hot reloaded
    publicPath: config.output.publicPath,
    quiet: true,

    // added this:
    watchOptions: {
      poll: 1000
    }
  })

Here were the settings I tried, and the resulting CPU usage:

poll: 1000  =>  4-6% CPU
poll: 500   =>  8-10% CPU
poll: 250   =>  14-16% CPU

There's a tradeoff between CPU usage and how snappy the dev experience feels. To me, 1000ms felt sluggish, but 500ms felt pretty good. I couldn't discern much difference between 500ms and 250ms.

It seems like adding some kind of polling interval would be a good idea to reduce the CPU usage.