:date: 2020-07-02

======================
Thursday, July 2, 2020
======================

Today I had some fun: my notebook computer didn't restart. It remained hanging
somewhere in the middle of the book process.

It took me some time to find out how to get into the rescue mode: hit ESC at
startup to activate the BIOS menu. There select "continue" and hold ESC key
again.

It then turned out that I had simply run out of disk space.

Okay my 20 years of private pictures and videos take 400 GB, but where is the
rest? What is taking up so much of my terabyte?

I used ``sudo baobab`` in order to see. And voilà, the guilty was Docker. Or
rather me, because I didn't read their docs which say clearly: "Docker takes a
conservative approach to cleaning up unused objects." In
:file:`/var/lib/docker/overlay` there was another 250GB of data. Each
:ref:`getlino` test run creates two new virtual Linux machines.  I simply said::

  $ sudo docker system prune
  WARNING! This will remove:
  - all stopped containers
  - all networks not used by at least one container
  - all dangling images
  - all dangling build cache

  Are you sure you want to continue? [y/N] y
  Deleted Containers:
  8e00fae0c56985e8a6ed10b147b52c2ac769aca9e7164dae1e6155f9f57b370f
  ...
  Deleted Images:
  deleted: sha256:093ab511c463ec62911de1d6f24f07b6be8072f1c87778f539bfc9c8f29f13f8
  ...
  Total reclaimed space: 201.7GB

Reviewed the :ref:`admin.du` page.