Hi,

We are using karaf 4.4.3 with equinox 3.18.200.v20221116-1324 on Windows
10 machines and we observe sometimes a very surprising effect of the
logging functionality on BundleActivator instances when restarting the
karaf server after a certain form of previous shut downs.

How to reproduce: Initially we observed the issue after some VM reboots
when the karaf server restarted, but found out that especially VMs with
not too much memory and/or a smaller number of cores can provoke this
situation in nearly 100% of all cases. We also found that the same issue
can be provoked more easily (on Windows) when killing the karaf Java
process in the task manager, sometimes only after the second or third
attempt of such provoked crashes followed by a restart.

How does it manifest: We found that under above described conditions
certain bundles that have registered a BundleActivator, don't show up
any more in the karaf logging. Interestingly an immediate declarative
OSGi service component in the same bundle (Which from a user point of
view has not much differences to a BundleActivator) did show logging, so
we could exclude the hypotheses, that the bundle was not started. In
fact, by triggering other observable side effects within
BundleActivator#start - such as creating a special marker file - we
could proof that the seemingly not executed BundleActivator#start *was*
in fact executed (The marker file was created), but no logging became
visible from the BundleActivator (as if logging would be disabled). We
found that all of org.slf4j.Logger, java.util.logging.Logger, and
org.osgi.service.log.Logger are affected by this, so we _assume_ that
the actual root may be related to a somewhat broken persisted state of
pax logging. But before we report that to the paxlogging project
directly, we would like to ask the karaf user group for possible hints
or ideas.

I should point out that we investigated this situation only for our own
bundles that are started rather early, but certainly after pax logging
has been started (No system bundles, just normal bundles).

I would appreciate any ideas or suggestions how to proceed.

Thanks,

- Daniel Krügler

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