Wowza Community

Wowza nDvr: possible reasons for getting "Too many packets in event queue"?

I am using Wowza streaming engine nDVR to record live streams, but I see a bunch of “Too many packets in event queue, pausing” log-warning messages in the daemon.log:

2018-05-30 10:24:30,953 [WARN] tVHost_.12 server comment LiveStreamDvrRecorderBase.addPacketizerEvent: Too many packets in event queue, pausing, errorCount:0 events:10001 lastEventTC:1527675734864 eventCount:536 processingEvent:true

2018-05-30 10:26:02,775 [WARN] VHost_.285 server comment LiveStreamDvrRecorderBase.addPacketizerEvent: Too many packets in event queue, pausing, errorCount:6750 events:10001 lastEventTC:1527675734864 eventCount:536 processingEvent:true

2018-05-30 10:26:06,405 [WARN] tVHost_.93 server comment LiveStreamDvrRecorderBase.addPacketizerEvent: Too many packets in event queue, pausing, errorCount:7000 events:10001 lastEventTC:1527675734864 eventCount:536 processingEvent:true

2018-05-30 10:26:09,704 [WARN] VHost_.184 server comment LiveStreamDvrRecorderBase.addPacketizerEvent: Too many packets in event queue, pausing, errorCount:7250 events:10001 lastEventTC:1527675734864 eventCount:536 processingEvent:true

2018-05-30 10:26:46,439 [INFO] stWatchdog server comment killUnidentifiedSessions: Killing unidentified session: address:/211.142.108.52:17179

2018-05-30 10:26:46,439 [INFO] stWatchdog server comment killUnidentifiedSessions: Killing unidentified session: address:/211.142.108.52:55544

What could be the reason for these log-messages?