4 ms·

Layers?

• guiriduro 8y ago
  But aren't they just an implementation detail, albeit a useful one? You'd find copy-on-write deltas in modern snapshotting filesystems too.
  • bboreham 8y ago
    Parent was comparing against a tarball, not a snapshotting filesystem.
  • jacques_chester 8y ago
    > But aren't they just an implementation detail, albeit a useful one? Part of what we do in Cloud Native Buildpacks is to use the layer abstraction more aggressively to make image updating more efficient. That requires taking care with the ordering and contents of each layer, so that they can be replaced individually. Putting it another way: we don't see the image as the unit of work and distribution. We're focused on layers as the central concept.
• whalesalad 8y ago
  Layers are each a tarball, extracted one by one on top of one another to get you to the end result.
  • RantyDave 8y ago
    So docker untars a filesystem which contains a file "foo" and calls this layer "1". Then it encounters a "RUN some_installer_thing" which removes file "foo" and calls this layer "2". If you just untar the layers on top of each other, foo will still be there. This is a problem, no?