Large number of 'layerschange' events with mediasoup 3.1.5

mediasoup libraries
1

Hi,

I just upgraded mediasoup from 3.1.0 to 3.1.5 and am now seeing 10-20 ‘layerschange’ events per second that affect only the temporalLayer, for every consumer with simulcast streams. There’s a noticeable impact on video framerate (so I don’t think that this is just a cosmetic warning I can ignore).

Bisecting my changes indicates that downgrading to 3.1.4 makes these go away. So does sending only a single encoding.

mediasoup:worker[pid:21853] RTC::Transport::ReceiveRtcpPacket() | no Consumer found for received Receiver Report [ssrc:905464878] +273ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 2 } +233ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 0 } +36ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 1 } +1ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 0 } +66ms
  mediasoup:worker[pid:21853] RTC::Transport::ReceiveRtcpPacket() | no Consumer found for received Receiver Report [ssrc:905464878] +263ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 2 } +160ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 0 } +31ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 1 } +0ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 0 } +72ms
  mediasoup:worker[pid:21853] RTC::Transport::ReceiveRtcpPacket() | no Consumer found for received Receiver Report [ssrc:905464878] +282ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 2 } +177ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 0 } +30ms
  demo-app consumer layerschange d93-483-083b->d93-483-083b cam-video { spatialLayer: 1, temporalLayer: 1 } +1ms

I’m not filing an issue because I’m assuming this is showing up some bad code on my part. :slight_smile: But I can file an issue if that’s helpful.

To reproduce:

  1. https://github.com/daily-co/mediasoup-sandbox.git
  2. cd mediasoup-sandbox/single-page/
  3. npm install
  4. DEBUG=“mediasoup*, demo-app*” npm run start
  5. open http://localhost:3000/ in a web browser
  6. click on “send camera streams”
  7. click on the “subscribe” button next to “my cam-video”
  8. see the debug messages from the ‘layerschange’ event handler in the server terminal window

Reproduces for me on Chrome 75.0.3770.80/Linux, Chrome 75.0.3770.100/OS X, Safari 12.1.1/OS X, Chrome 75.0.3770.100/Windows, and Firefox 67.0.1/Windows.

Here are the mediaCodecs passed to worker.createRouter():

      mediaCodecs:
        [
          {
            kind: 'audio',
            mimeType: 'audio/opus',
            clockRate: 48000,
            channels: 2
          },
          {
            kind: 'video',
            mimeType: 'video/VP8',
            clockRate: 90000,
            parameters:
              {
//                'x-google-start-bitrate': 1000
              }
          }

And here are the simulcast encodings I’m passing to transport.produce() (all the encodings I’ve tried seem to have this same behavior, though):

[
  { maxBitrate:  96000, scaleResolutionDownBy: 4 },
  { maxBitrate: 680000, scaleResolutionDownBy: 1 },
]
2

Let’s some days to come to this, please. Super busy now.

3

Please, report it in GitHub. I see the very same problem in the official demo so something is wrong.

4

Also, please indicate that it happens in both VP8 and H264 simulcast, but it does not happen in VP9 SVC.

5

No need to report it, I see the bug. Will be fixed soon.

6

Reported.

7

Fixed in https://github.com/versatica/mediasoup/commit/ca3166026f420c3dbe3c0e3e39aa2a9f13abe726. Released in 3.1.6.

Many thanks.

1 Like