Running Webpack-dev-server in docker is significantly slower than on local machine

Question

I'm moving most of my development processes into docker to ensure a parallel development environment between computers so there are no odd bugs or issues due to version mis-match, etc.

All of this is going great, except that when running webpack-dev-server inside of docker, the build process is substantially slower than when I run it just locally on my computer. (Like 3-5 minutes in docker vs 30 seconds to 1 min locally). Is there any way to speed this up? Is it just an issue with docker/webpack interacting with a lot of files on my hard drive through a mounted volume?

If it matters, my host system is a Mac running High Sierra on an i7 with 16bg of ram.

I'm running docker for mac, docker -v returns: Docker version 17.12.0-ce, build c97c6d6

I hope all of this is clear enough, let me know if I can add any information!

Answer 1

For those in a similar spot, as Matt suggested, the issues were coming from having a mounted volume. I sped the build up significantly by using docker's volume cache mode. The docs on it are here.

The command looks something like this:

docker run -v \local\director:docker\directory:cached dockerImage

Answer 2

I would recommend using delegated instead of cached as per the documentation:

Cached: The host is authoritative in this case. There may be delays before writes on a host are available to the container.

Delegated: The container is authoritative. There may be delays until updates within the container appear on the host.

So the docker-compose file would be as following:

version: '3'
services:
  front:
    container_name: my-front-dev
    image: my-front-dev-image
    build:
      context: .
      dockerfile: front/Dockerfile.dev
    ports:
      - 5002:80
    volumes:
      - ./front/:/app/:rw:delegated