Add potato image and BTRFS cleanup blog post, update image references

content/2025-10-09-webwords-reaches-42-languages-the-ultimate-programming-kata.rst

@@ -21,7 +21,7 @@ the spec
 Every implementation does exactly the same thing:
 
 1. Accept two query parameters: ``keyword`` and ``target``
-2. Fetch the content from the target URL
+2. Fetch the content from the target URI
 3. Search for the keyword in that content
 4. Return ``true`` or ``false`` as plain text
 
@@ -36,6 +36,11 @@ To test any implementation, try searching for ``potato`` on `Remarkbox <https://
 
 Returns ``true`` because potato exists on Remarkbox.
 
+.. image:: /uploads/2025/10/potato.jpg
+   :alt: Potato
+   :align: center
+   :width: 480px
+
 the implementations
 ===================
 

content/2025-10-10-unpotato-webwords-btrfs-cleanup-docker-volumes.rst

@@ -0,0 +1,117 @@
+unpotato webwords: cleaning up btrfs docker volumes after build-all
+###################################################################
+
+:author: Russell Ballestrini
+:slug: unpotato-webwords-btrfs-cleanup-docker-volumes
+:date: 2025-10-10 14:00
+:tags: Code, DevOps, Docker, BTRFS
+:status: published
+
+So you ran ``make build-all`` on webwords and now your root filesystem is 100% full. BTRFS doesn't clean up Docker volumes the way you'd expect. Here's how to unpotato your system.
+
+.. image:: /uploads/2025/10/potato.jpg
+   :alt: Potato
+   :align: center
+   :width: 480px
+
+.. contents::
+
+the problem
+===========
+
+Docker's ``system prune`` doesn't fully clean up BTRFS subvolumes. Even after removing containers and images, the filesystem usage stays high because the underlying BTRFS subvolumes persist.
+
+identify docker volumes
+========================
+
+List all Docker volumes:
+
+.. code-block:: bash
+
+ docker volume ls
+
+Check which containers might be using volumes:
+
+.. code-block:: bash
+
+ docker ps -a --filter volume=volume_name
+
+delete docker volumes
+======================
+
+Stop and remove any containers using the volumes:
+
+.. code-block:: bash
+
+ docker stop $(docker ps -aq)
+ docker rm $(docker ps -aq)
+
+Remove all unused volumes:
+
+.. code-block:: bash
+
+ docker volume prune -f
+
+manual btrfs cleanup
+====================
+
+If filesystem usage is still high, manually clean up BTRFS subvolumes.
+
+Check Docker's storage driver:
+
+.. code-block:: bash
+
+ docker info --format '{{.Driver}}'
+
+If it shows ``btrfs``, locate the subvolumes:
+
+.. code-block:: bash
+
+ sudo ls /var/lib/docker/btrfs/subvolumes/
+
+List all BTRFS subvolumes:
+
+.. code-block:: bash
+
+ sudo btrfs subvolume list /var/lib/docker
+
+Delete persistent subvolumes:
+
+.. code-block:: bash
+
+ sudo btrfs subvolume delete /var/lib/docker/btrfs/subvolumes/HASH_HERE
+
+Wait for async deletion to complete:
+
+.. code-block:: bash
+
+ sudo btrfs subvolume sync /var/lib/docker
+
+nuclear option
+==============
+
+If manual cleanup doesn't work, stop Docker and remove everything:
+
+.. code-block:: bash
+
+ sudo systemctl stop docker
+ sudo rm -rf /var/lib/docker
+ sudo systemctl start docker
+
+This will delete all Docker data including images, containers, and volumes.
+
+verify cleanup
+==============
+
+Check filesystem usage:
+
+.. code-block:: bash
+
+ df -h /
+
+The usage should drop significantly after proper cleanup.
+
+prevention
+==========
+
+Consider using a separate filesystem for Docker or configuring Docker to use a different storage driver if you frequently build large numbers of containers on BTRFS.