Docker - All the Magic

Understanding It

• docker is a history recorded of what changed from the original image that the container started off
• restart (or stop and start) reverts the container to what the image was, so the container is transient by default
• it may be also possible to revert by tagging the image (yes!)
  

Maintenance

When it gets sloooow, and the com.docker.hyperkit takes 20% or 30% of CPU or more, try:

• consider reducing the # of cpu's enabled
• prune images not referenced by any container (created
  more than 24h ago):
  

  docker image prune -a --filter "until=24h"

• prune containers all stopped containers (older than 24h):

  docker container prune --filter "until=24h"

• prune networks not used by any container (older than 24h):

  docker network prune --filter "until=24h"

• and possibly prune volumes not used by currently by any container (make sure you don't need the data on them):

  docker volume prune