Task org.apache.jackrabbit.oak.commons.concurrent.NotifyingFutureTask@5aa22536[Not completed, task = org.apache.jackrabbit.oak.spi.commit.BackgroundObserver$1$1@5e9daa3d] rejected from java.util.concurrent.ThreadPoolExecutor@1fa0a006[Shutting down, pool size = 1, active threads = 1, queued tasks = 0, completed tasks = 2]