Qjournalctl can show you the amount of disk space taken up by your journal.
This is accessed from the menu “journalctl | Size of the journal on disk”.
Other features include:
- Reverse the journalctl output.
- Export the filtered journal or the current selection.
- Show the complete journal.
- Autocompletion for filtering by syslog identifiers. When loading the journal, a list of all identifiers is created.
- Display the log size additionally in bytes.
- Keyboard shortcuts.