Image size reported as 1e+03MB by `docker image ls`

[rmunn]

Description

When creating a Docker image that was almost, but not quite, 1 billion bytes in size, I noticed that docker image ls reported the size as 1e+03MB instead of 1000MB or 1.0GB. I figure that what happened is that the image was less than 1000MB so it didn't get reported as 1.0GB, but then since it was more than 999.5MB, it didn't get reported as 999MB either. This isn't really a problem for me, but it was slightly jarring, and I could conceive of a possible issue where someone's script designed to parse the output of docker image ls might barf on an unexpected format for image size.

I did not find any duplicate issues reporting this, probably because it's rare to actually trigger the conditions for this to happen, so I figured I'd report it so that someone can figure out a fix.

Steps to reproduce the issue:

1. Create an image between 999,500,000 bytes and 1,000,000,000 bytes in size (mine was 999,517,084 bytes)
2. Run docker image ls
3. Note size is reported as 1e+03MB

Describe the results you received:

REPOSITORY                       TAG                    IMAGE ID       CREATED          SIZE
tmp-deb-full                     latest                 5fbf6884916b   9 minutes ago    1e+03MB

Describe the results you expected:

REPOSITORY                       TAG                    IMAGE ID       CREATED          SIZE
tmp-deb-full                     latest                 5fbf6884916b   9 minutes ago    1000MB

Additional information you deem important (e.g. issue happens only occasionally):

My Dockerfile that produced this result:

FROM debian:sid

COPY apt-sources.list /etc/apt/sources.list
RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y devscripts cli-common-dev sbuild

I ran this on 2021-05-12 around 06:00 UTC. Reproducing the exact image I produced might be difficult since any new packages uploaded to Debian sid (whcih gets new packages uploaded all the time) would very likely have a different size and end up with a different image size, and I suspect the bug is triggered only when image size is >= 999.5MB and < 1000.0MB. Therefore, I preserved the image in question with docker image save. The .tar.xz file is 275 MB, so I won't attach it to this issue, but I can upload it somewhere and make it available on request, if anyone needs it. (Though I suspect one could repro this issue by creating an image full of zero bytes, so you may not need it.)

I've also included the output of docker image inspect below in case it helps.

Output of docker image inspect

[
    {
        "Id": "sha256:5fbf6884916b3cb9b4fd34e322553befe10df7ad285d217d06cd0dfe1754153e",
        "RepoTags": [
            "tmp-deb-full:latest"
        ],
        "RepoDigests": [],
        "Parent": "sha256:fa5df1ab58fe6d662ddefe3a92d9bb8a34f685e45de6ab1812ab37b880cc5a74",
        "Comment": "",
        "Created": "2021-05-12T05:50:53.620376318Z",
        "Container": "ff4ab78243d481861dc73a740b8e3217b713dd603d5656a114139ba84f8992b4",
        "ContainerConfig": {
            "Hostname": "",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
            ],
            "Cmd": [
                "/bin/sh",
                "-c",
                "apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y devscripts cli-common-dev sbuild"
            ],
            "Image": "sha256:fa5df1ab58fe6d662ddefe3a92d9bb8a34f685e45de6ab1812ab37b880cc5a74",
            "Volumes": null,
            "WorkingDir": "",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": null
        },
        "DockerVersion": "20.10.2",
        "Author": "",
        "Config": {
            "Hostname": "",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
            ],
            "Cmd": [
                "bash"
            ],
            "Image": "sha256:fa5df1ab58fe6d662ddefe3a92d9bb8a34f685e45de6ab1812ab37b880cc5a74",
            "Volumes": null,
            "WorkingDir": "",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": null
        },
        "Architecture": "amd64",
        "Os": "linux",
        "Size": 999517084,
        "VirtualSize": 999517084,
        "GraphDriver": {
            "Data": {
                "LowerDir": "/var/lib/docker/overlay2/9074e34a9e7c1509ee5fe460707f6b18ed4398a484c359e716a7cd2e0c41d039/diff:/var/lib/docker/overlay2/fb68e8329c72acc7836a2a28400c387527f8ffad147962373dacb8052df2c13a/diff",
                "MergedDir": "/var/lib/docker/overlay2/ef54d02d58c48a2d89cbe9d63026ca554177fe115690896e2c9731045159055b/merged",
                "UpperDir": "/var/lib/docker/overlay2/ef54d02d58c48a2d89cbe9d63026ca554177fe115690896e2c9731045159055b/diff",
                "WorkDir": "/var/lib/docker/overlay2/ef54d02d58c48a2d89cbe9d63026ca554177fe115690896e2c9731045159055b/work"
            },
            "Name": "overlay2"
        },
        "RootFS": {
            "Type": "layers",
            "Layers": [
                "sha256:ae0a22915636881ac7024d0fcf1d828d913a6cb0b243baa1d20fead12be078a7",
                "sha256:2ab3f25d2804db9d2956cf35119c667aa794bce981ba0b590efe1291d7469e42",
                "sha256:1adc272ccaf3b3dc95e69f351db9a509d0ea607df07c8cdc6e226ee95ae32210"
            ]
        },
        "Metadata": {
            "LastTagTime": "2021-05-12T12:50:54.522154763+07:00"
        }
    }
]

Output of docker version:

Client:
 Version:           20.10.2
 API version:       1.41
 Go version:        go1.13.8
 Git commit:        20.10.2-0ubuntu1~18.04.2
 Built:             Tue Mar 30 21:24:16 2021
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server:
 Engine:
  Version:          20.10.2
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.8
  Git commit:       20.10.2-0ubuntu1~18.04.2
  Built:            Mon Mar 29 19:27:41 2021
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.3.3-0ubuntu1~18.04.4
  GitCommit:        
 runc:
  Version:          spec: 1.0.2-dev
  GitCommit:        
 docker-init:
  Version:          0.19.0
  GitCommit:        

Output of docker info:

Client:
 Context:    default
 Debug Mode: false

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 173
 Server Version: 20.10.2
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 io.containerd.runtime.v1.linux runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 
 runc version: 
 init version: 
 Security Options:
  apparmor
  seccomp
   Profile: default
 Kernel Version: 5.4.0-72-generic
 Operating System: Linux Mint 19.1
 OSType: linux
 Architecture: x86_64
 CPUs: 12
 Total Memory: 62.58GiB
 Name: REDACTED
 ID: REDACTED
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  localhost:32000
  127.0.0.0/8
 Live Restore Enabled: false

WARNING: No swap limit support
WARNING: No blkio weight support
WARNING: No blkio weight_device support

Additional environment details (AWS, VirtualBox, physical, etc.):

[rmunn]

Still occurs with Docker 20.10.8, running on Ubuntu 21.10.

Output of docker version on my Ubuntu 21.10 test VM:

Client: Docker Engine - Community
 Version:           20.10.8
 API version:       1.41
 Go version:        go1.16.6
 Git commit:        3967b7d
 Built:             Fri Jul 30 19:53:57 2021
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.8
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.16.6
  Git commit:       75249d8
  Built:            Fri Jul 30 19:52:06 2021
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.9
  GitCommit:        e25210fe30a0a703442421b0f60afac609f950a3
 runc:
  Version:          1.0.1
  GitCommit:        v1.0.1-0-g4144b63
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

Output of docker info on my Ubuntu 21.10 test VM:

Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker App (Docker Inc., v0.9.1-beta3)
  buildx: Build with BuildKit (Docker Inc., v0.6.1-docker)
  scan: Docker Scan (Docker Inc., v0.8.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 2
 Server Version: 20.10.8
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 io.containerd.runtime.v1.linux runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: e25210fe30a0a703442421b0f60afac609f950a3
 runc version: v1.0.1-0-g4144b63
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: default
 Kernel Version: 5.11.0-20-generic
 Operating System: Ubuntu Impish Indri (development branch)
 OSType: linux
 Architecture: x86_64
 CPUs: 2
 Total Memory: 971.7MiB
 Name: ubuntu-impish
 ID: FOPY:SQMP:IOHW:CLZA:IAM2:IVWA:E5IY:AHE6:OVHF:LOZO:2CPL:PHGN
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

[ThelonKarrde]

I second this, not a big deal but looks weird.

➜  docker --version
Docker version 20.10.17, build 100c701
➜  uname -a
Linux blackstar 5.4.0-107-generic #121-Ubuntu SMP Thu Mar 24 16:04:27 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

➜  git:(master) docker images
REPOSITORY                     TAG                       IMAGE ID       CREATED          SIZE
nvidia/nvidia-driver-flatcar   470.103.01                0931e1f8d96c   50 minutes ago   1e+03MB

[LyndonArmitage]

Just saw this on my Manjaro Linux machine:

Docker version 23.0.1, build a5ee5b1dfc

Client:
 Version:           23.0.1
 API version:       1.42
 Go version:        go1.20
 Git commit:        a5ee5b1dfc
 Built:             Sat Feb 11 13:58:04 2023
 OS/Arch:           linux/amd64
 Context:           default

Server:
 Engine:
  Version:          23.0.1
  API version:      1.42 (minimum version 1.12)
  Go version:       go1.20
  Git commit:       bc3805a0a0
  Built:            Sat Feb 11 13:58:04 2023
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          v1.6.16
  GitCommit:        31aa4358a36870b21a992d3ad2bef29e1d693bec.m
 runc:
  Version:          1.1.4
  GitCommit:        
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

[GiorgioAresu]

Hi, I'd like to give this a go. I already made a sample image to reproduce it and I'm setting up the environment

[kmirzavaziri]

I hope fixing this issue on docker go-units fixes this.

[athulnair02]

Hi, I'm from the UT Austin virtualization class, and as part of our open-source project, I'd like to take on this issue if possible. Given that it is labeled as a beginner issue, it would fit into my current open-source contribution experience.
Thanks!