I run a couple of Docker containers running Jenkins. They do quite a bit of I/O, downloading artefacts, building etc. If I do a du -sh inside the container I can see they consume lets say 12GB of space. But if I delete the container and check the docker data space metrics I free up much more space than that ( 40 GB or so). Why are the containers consuming that much storage? Will space never be reclaimed?
It is really annoying since after a while all my data space is being consumed and the containers stop working.
Just a guess not knowing much details, are you using just the default loop back device mapper storage driver configuration? as that may be your problem, ie something to do with how device mapper uses it’s sparse file
FYI this is a good read and some links to some other good reading material.