Home assistant database locked again

Configuration
15

@pnbruckner My memory use has levelled off at between 50% and 55% (pi3B with 1GB).

@Mariusthvdb, settings below:

configuration.yaml:

 recorder:
  db_url: !secret mariadb_url
  purge_interval: 1
  purge_keep_days: 7

secrets.yaml:

mariadb_url: mysql://hass:my_redacted_password@core-mariadb/homeassistant

Mariadb config:

{
  "databases": [
    "homeassistant"
  ],
  "logins": [
    {
      "username": "hass",
      "host": "homeassistant",
      "password": "my_redacted_password"
    }
  ],
  "rights": [
    {
      "username": "hass",
      "host": "homeassistant",
      "database": "homeassistant",
      "grant": "ALL PRIVILEGES ON"
    }
  ]
}