Reco wrote:
> You haven't took into account journald, which uses /run (mounted
> in-memory) to write its' own blobs. With the limit of 1/2 of available
> physical memory by default.
That's wrong by nearly 2 orders of magnitude..
journald avoids using more than 10% of the size of /run by default,
and the size of /run is 20% of physical memory.
So, on a system with 4 gb of memory, it uses not 2 GiB, but 77 MiB.
Sep 29 13:35:43 darkstar systemd-journal[169]: Runtime journal is using 8.0M (max allowed 76.9M, trying to leave 115.4M free of 761.3M available → current limit 76.9M).
A system with 128 MiB of memory would have 1.3 MiB used for the journal.
That's less memory than the (non-shared) memory used by bash to log into
such a low memory system. But if it did become a problem, there's a
simple config file to tune it, which has an excellent man page.
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. SystemKeepFree= and
RuntimeKeepFree= control how much disk space systemd-journald shall
leave free for other uses. systemd-journald will respect both
limits and use the smaller of the two values.
The first pair defaults to 10% and the second to 15% of the size of
the respective file system.
--
see shy jo