VHDX size is huge! 5.5GB vhdx vs ~450 MB images+volumes

Hello.

  • Issue type: Disk Size
  • OS Version/build: Windows 10 LTSC / 17763.678
  • App version: Docker version 19.03.8, build afacb8b

I’m newbie on docker… have only 3 small images, as you can see here:

$ docker images -a
REPOSITORY              TAG               MAGE ID         CREATED           SIZE
hasura/graphql-engine   v1.2.0-beta.2    7bbdfd8b72b7     9 days ago        42.1MB
postgres                12               73119b8892f9     9 days ago        314MB
hasura/graphql-engine   v1.1.0           d244a461a2d3     3 weeks ago       41.3M

$ docker system df
TYPE                TOTAL            ACTIVE              SIZE               RECLAIMABLE
Images              3                3                   397MB              0B (0%)
Containers          3                3                   124B               0B (0%)
Local Volumes       1                1                   51.75MB            0B (0%)
Build Cache         0                0                   0B                 0B

But my vhdx disk has about 5.5 G size. How this is possible ?