systemd has its own logging system which provides centralized management for logging kernel and userland processes. This article explains how to clear the systemd journal log files.systemd-journald is a system service that collects and stores logging data. This log data is stored either in
/run/log/journal/MACHINE-ID/ (volatile - the journal log data is stored in memory and is lost on reboot) or in
/var/log/journal/MACHINE-ID (persistent - the journal data log is stored on disk). On systems which are configured to store the systemd journal data on disk, the logs can take a considerable amount of disk space after some time.
