Today my unRaid 6.7.0 spit out a warning about my docker.img.

Docker high Image disk utilization: [date and time]
Warning [name of my server] - Docker Image disk utilization of 77% 
Docker utilization of image file
/mnt/user/system/docker/docker.img

I was looking in the path stated in the warning and found my docker.img with a size of about 21 GB. What makes me wonder, is the fact, that using the button "Container Size" under the Docker-Tab gives me a cumulated size of about 11 GB on all containers installed. Where does a difference of 10 GB come from?

Running "docker.ps" in the console also does not show anything that seems to be suspicious.

Scrubing the docker.img in the Dashboard-tab also did not output any errors, alerts or something to work with.

 

Any hints or suggestions on that matter?

Is there a way or a command to inspect or show the content of the docker.img?

 

Thanks in advance!

 

 

Edited June 13, 20197 yr by hi2hello

I guess I found the answere here: 

 

Also noticed that the docker.img size gets allocated to a fixed image size which is what I can see in the file system while "Container Size" just gives out what is really installed. Obvious that there must be a difference.

Stopped the docker.img and rised allocation size from 20 to 30GB, so everything is set back to normal for now and the warning disappeard.

 

There is just one little thing that still makes me wonder: If the content of the docker.img is about 12 GB and the allocated size is 20 GB, how can it be that I get a warning about 77% of usage? If I do calculate roughly, it would be around 60%.

Current usage of the docker now shows 49%, although 12 from 30 GB makes 40%. Is this just a calculation error?

 

Also still would like to know if there is a way to have a look into the content of the docker.img

 

Any answers and explanations on that matter still more than welcome!

 

 

 

Edited June 13, 20197 yr by hi2hello
finetuned

Docker Logs maybe? There is overhead in the docker image because of all the layers it has to do, so there is some space lost to that, think of it like file-system overhead.

 

I have less than 3 GB used on my Docker Image of 15 GB from nearly 3 years of usage with usenet, torrents, and a media server included. If you have rapid docker usage growth without new installations, you have something misconfigured.