This is more readable than passing arguments to the daemon directly. It
also shortens the ExecStart command significantly, which is stored in
every log entry in systemd-journald.
It seems that Docker can fail to start if there is no space left on the
device. Try to free up some space in that case by asking journald to
limit its size to 256MiB.
This should work for any storage larger than ~2.5GiB (as the journals
maximum size is 10% of the disk size). It still should leave enough
logs to diagnose problems if necessary.
Note: We could also limit the size of the journal in first place, but
that isn't sustainable: Once that space is used up, we run into the
same problem again.
By only asking journalctl to free up if necessary, we kinda (miss)use
the journal as way to "reserve" some space which we can free up at boot
if necessary.
* Disable real-time scheduling
It seems that Linux' cgroup v2 currenlty does not support RT scheduling.
* Remove Supervisor RT support flag
With CGroups v2 we can no longer support CPU resource allocation for
realtime scheduling.
* Bump OS Agent to 1.3.0 for CGroups v2 support
* Avoid duplicate log entries
So far the hassos-supervisor.service starts the hassos-supervisor script
which in turn attaches to the Supervisor container. This causes stdout
and stderr to be forwarded to the service unit, which in turn logs it in
the journal.
However, Docker too logs all stdout/stderr to the journal through the
systemd-journald log driver.
Do not attach to the Supervisor container to avoid logging the
Supervisor twice.
Note that this no longer forwards signals to the container. However, the
hassos-supervisor.service uses the ExecStop= setting to make sure the
container gets gracefully stopped.
* Use image and container name as syslog identifier
By default Docker users the container id as syslog identifier. This
leads to log messages which cannot easily be attributed to a particular
container (since the container id is a random hex string).
Use the image and container name as syslog identifier.
Note that the Docker journald log driver still stores the container id
as a separate field (CONTAINER_ID), in case the particular instance need
to be tracked.
* Add --cpu-rt-runtime to allow Docker allocate real-time CPU time (#1235)
* Enable Supervisor's CPU bandwith allocation feature (#1235)
Since we have CONFIG_RT_GROUP_SCHED enabled in the Home Assistant OS
kernel the Supervisor needs to enable CPU bandwith allocation for
Add-Ons which need real-time scheduling. Set the appropriate environment
variable.
