"Request to the Service Monitor failed. This may cause slow page responses"
And the logs show the following:
com.cloudera.enterprise.debug.JvmPauseMonitor: Detected pause in JVM or host machine (e.g. a stop the world GC, or JVM not scheduled): paused approximately 3687ms: GC pool 'ParNew' had collection(s): count=1 time=0ms, GC pool 'ConcurrentMarkSweep' had collection(s): count=1 time=3876ms
Increase heap for the Service monitor and restart the service would be the first thing to try.