A systemd bug report opened on January 3, 2026, put a number on something Linux admins had long suspected: systemd-journald writes far more data to disk than the log text it stores. The reporter, running systemd 257.9 on Debian 13 (kernel 6.12.57+deb13-amd64) with the journal on XFS, saw a virtual machine doing about …

On a systemd-based VPS the journal is not a plain text file you can tail and forget — it is a structured, indexed binary store managed by systemd-journald, and left at its defaults it will quietly grow until it claims a slice of your disk you never agreed to give it. That structure is a feature, not an annoyance: every …