Is this plugin useful now that Webpack 4 has a parallel option?

[Sawtaytoes]

I noticed parallelism listed in Webpack 4's config. What benefit does HappyPack offer now that I'm seeing parallelism as a native Webpack config value?

Source: https://webpack.js.org/configuration/other-options/#parallelism

[henopied]

@Sawtaytoes That option seems to have to do with how many modules are processed on the main thread rather than on separate threads. Edit: However, due to how happypack can process many more modules at once, it may be logical to increase that to allow for happypack to really use those threads.

[Sawtaytoes]

What would that look like? Currently, I have HappyPack using as many threads as are available in os.cpus().length.

[yyynnn]

Well i see no improvement with webpack 4

[HopperGithub]

I plan to remove it when upgrading webpack 4

[misterfresh]

I was about to post the same issue. In Task Manager monitoring tool, with Webpack 3 I noticed only one thread active. With webpack 4 I noticed 4 cores/ 8thread active when compiling. So is there still a benefit to using happypack with webpack 4?

[grzegorzjudas]

I noticed, without using Happypack, that Webpack 4.16.4 is indeed using multiple threads:

I wanted to test whether using Happypack would result in decreased build time, however I wasn't able to make it work:

ERROR in ./index.tsx
Module build failed (from ../node_modules/happypack/loader.js):
Error: You may be using an old version of webpack; please check you're using at least version 4

even though I'm using webpack 4.

[mjlangan]

@grzegorzjudas Did you ever figure this out? I wanted to try the same experiment with adding Happypack to our Webpack 4 config, and am running into the exact same error.

[JE-lee]

webpack v4 take parallel process acquiescently

[grzegorzjudas]

@mjlangan I did not - figured the semver/regex that detects the webpack version used in happypack is incorrect/out-of-date.

I recommend trying out most recent version of happypack and if it's still there, raising an issue for happypack. I removed happypack myself, since the most important thing for me (multithreading) is working just fine without it.