Docker saving gives double size

Open Source Projects DockerEngine
1

Having built a dockerfile, the image size in docker is about the expected, 13,7 gb. However if i “docker save” the image, it becomes a 26 gb file? How is this possible? I want to save it, so another docker machine can load it and make containers from it.

(Guess is that it includes base image in image saved)

# escape=`

FROM microsoft/dotnet-framework

SHELL ["powershell", "-Command", "$ErrorActionPreference = 'Stop'; $ProgressPreference = 'SilentlyContinue';"]

# Install .NET Core
ENV DOTNET_VERSION 2.1.2

RUN Invoke-WebRequest -OutFile dotnet.zip https://dotnetcli.blob.core.windows.net/dotnet/Runtime/$Env:DOTNET_VERSION/dotnet-runtime-$Env:DOTNET_VERSION-win-x64.zip; `
    $dotnet_sha512 = '9e67c62feb34aeb52a45d0e623d1ad098637a322545956eb5e6de2287ddad2412b766c492ae5a7dddc123a4cb47cfc51d9bb10d0e30c007ec3fc90666f9733c8'; `
    if ((Get-FileHash dotnet.zip -Algorithm sha512).Hash -ne $dotnet_sha512) { `
        Write-Host 'CHECKSUM VERIFICATION FAILED!'; `
        exit 1; `
    }; `
    `
    Expand-Archive dotnet.zip -DestinationPath $Env:ProgramFiles\dotnet; `
    Remove-Item -Force dotnet.zip

RUN setx /M PATH $($Env:PATH + ';' + $Env:ProgramFiles + '\dotnet')

# Configure Kestrel web server to bind to port 80 when present
ENV ASPNETCORE_URLS=http://+:80 `
# Enable detection of running in a container
DOTNET_RUNNING_IN_CONTAINER=true

WORKDIR /app
COPY /app .

ENTRYPOINT & "/app/web.exe"