Очистка /var/log/journal/

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SystemMaxUse=, SystemKeepFree=, SystemMaxFileSize=, RuntimeMaxUse=, RuntimeKeepFree=, RuntimeMaxFileSize=
           Enforce size limits on the journal files stored. The options prefixed with "System" apply to the journal files when stored on a
           persistent file system, more specifically /var/log/journal. The options prefixed with "Runtime" apply to the journal files when stored
           on a volatile in-memory file system, more specifically /run/log/journal. The former is used only when /var is mounted, writable, and the
           directory /var/log/journal exists. Otherwise, only the latter applies. Note that this means that during early boot and if the
           administrator disabled persistent logging, only the latter options apply, while the former apply if persistent logging is enabled and
           the system is fully booted up.  journalctl and systemd-journald ignore all files with names not ending with ".journal" or ".journal~",
           so only such files, located in the appropriate directories, are taken into account when calculating current disk usage.
           SystemMaxUse= and RuntimeMaxUse= control how much disk space the journal may use up at maximum. Defaults to 10% of the size of the
           respective file system.  SystemKeepFree= and RuntimeKeepFree= control how much disk space systemd-journald shall always leave free for
           other uses. Defaults to 15% of the size of the respective file system. systemd-journald will respect both limits, i.e. use the smaller
           of the two values.  SystemMaxFileSize= and RuntimeMaxFileSize= control how large individual journal files may grow at maximum. This
           influences the granularity in which disk space is made available through rotation, i.e. deletion of historic data. Defaults to one
           eighth of the values configured with SystemMaxUse= and RuntimeMaxUse=, so that usually seven rotated journal files are kept as history.
           Specify values in bytes or use K, M, G, T, P, E as units for the specified sizes (equal to 1024, 1024²,... bytes). Note that size limits
           are enforced synchronously when journal files are extended, and no explicit rotation step triggered by time is needed.
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