Wowza Community

Live Stream Pausing every 10 Sec

I currently use a Wowza Server that is provided and supported by a third party, the issue below does not exist on our current production server using the same configuration.

I’m setting up Wowza on a hosted server to self-manage and have an issue with the higher quality live stream pausing about every 10-11 sec, this same stream configuration works without issue for VOD.

Server has 32 cores, 64GB Memory, +10 Gigabit NIC.

I’m publishing via rtmp two multi bitrate streams using a smil file for playback with jw player:

This configuration works with no pausing:

800Kb/64Kb

500Kb/64Kb

250Kb/64Kb

This configuration has the pausing issue:

2800Kb/128Kb

2000Kb/128Kb

1400Kb/128Kb

I’ve looked at all the setting for the live application and performance tuning but not seeing exactly what needs to change to resolve this issue.

Kirk

What encoding profile are you using and have you tried changing that? Are you using JW Player on a mobile phone?

Higher Quality stream may require main or high:

Videos encoded with baseline profile can be easily played back, even on devices with lower computational power, such as older smartphones. Android and iOS phones, for example, officially only play video encoded with the baseline profile, but not High or Main. This has changed a little bit in the last years, where more and more phones can actually play main or high profile video, but still the official recommendations don’t mention that.

You are publishing RTMP but are you converting it to HLS for playback? If so, you can adjust your video chunk sizes and min required number of chunks improving playback.

Sounds like either not enough CPU or packets need to be adjusted. Anything from the logs?

Thanks Rose,

First, I have been using this configuration for over 5 years on our current production server which is using Wowza so I’m assuming the encoder setup is fine.

Our new hosted server has 32 physical cores and 64 logical processors and with the live stream running averages about 20% utilization (that includes any VOD usage since I have enabled all our content on this server).

I do have H.264 set to Main at 3.1, the other encoder publishing the lower bitrates is using baseline at 3.0.

I think my player config is rtmp over http if I understand it correctly with HLS if no Flash.

I did try the HLS settings from the link you provided and removed the the first url source and that does seem to work better but at the start (each refresh) it seems to start at an earlier point and then pauses and jumps forward to what I’m assuming is the current progress point of the stream.

This is the player and smil config:

JW Player 7.12.13:

Smil File:

<?xml version="1.0" encoding="UTF-8"?>

Thank you. Tech support would like to see a support ticket on this as they suspect something is off with the chunk packetizers, but too difficult to tell without full access to your config and logs.

Can you send one in and we will get it straightened out for you?

https://www.wowza.com/support/open-ticket

Ok, for the config do you mean what I posted above or the config on the server?

If the server config how do I sent that?

I see what is needed in the ticket details, submitting now…

Great! Thank you…

I submitted the ticket and now I’m trying out the Transcoder option which is not something I’ve used before and have a few questions.

I have a live stream running configured with all the bitrates I normally stream for live (mostly the ones listed above).

The source is 2800/128 and I have 7 other options in the template, the URL points to the group, “ngrp:jzkLive_all”.

With this configuration I do not have the pausing issue with the higher bitrate streams that I have when I individually publish each bitrate to the server.

Questions:

Is using the Transcoder option a more efficient usage of server resources over my current method of publishing all bitrates for the encoders?

Does the Transcoder increase latency?

Currently I’m using the group url, is there an advantage to using a smil file for the adaptive config?

Are there any drawbacks to the Transcoder to be considered?

Thanks,

Kirk

Is using the Transcoder option a more efficient usage of server resources over my current method of publishing all bitrates for the encoders?

Answer: Yes, because it is creating the optimal resolutions as well as optimal bitrates and is much cleaner process between the media server and the player who can quickly access a SMIL file and make necessary switches. SMIL file also can better control chunk sequence and provide a cleaner ABR output stream.

Does the Transcoder increase latency?

Answer:

Not by very much no. It will be much faster than how you are submitting the info because all the different renditions of the stream are keyframe aligned which is MANDATORY for smooth adaptive bitrate streaming. The players can only switch bitrates at a keyframe so if your other renditions were not keyframe aligned, that may have been the reason you were experiencing the pauses. The player had to catch up and wait for a keyframe to make the switch.

****Using the transcoder is more efficient for you and for the player. I hope that helps!

Here is out video tutorial on it and I think there are more on You Tube:

https://www.youtube.com/watch?v=E4YvKAFbmQc

Great, so far it’s working well and I will stay with this solution for live streaming.

One last question:

We have many users that only have DSL service available to them and some have slower than normal DSL speeds, and also some with only satellite service in more rural areas around the world.

I currently use adaptive bitrate using JW7 and have a Hi Q player option for bitrates above 1000Kb and a Med Q player option with bitrates below 1000Kb.

I have found having all the bitrates in one player can be problematic for those on slow connections because the video will something not auto adapt down at start so the video will not load and the “HD” menu never becomes available to select a lower bitrate.

If I continue with this setup is there any advantage to having two transcoder templates for publishing a higher bitrate source stream for the Hi Q player and a lower bitrate source stream for the Med Q player, OR is just the one higher bitrate source stream sufficient and then use two different smil files for the approperate bitrates for each player?

Thanks again,

Kirk

One more question concerning nDVR and Stream Record.

Our current provider had setup a separate application for us to stream for DVR Playback and to record that content to an MP4 file.

Of course the result of that was we were publishing two complete sets of all the bitrates since the Live Stream and DVR/Record were separate applications (and we did not know there was a transcoding option).

I also started that same setup but wondered if I could just enable on the transcoder application, so I tried that and it works to provide the preset bitrates not just the source which I thought it might.

I wonder if the setup we have been using is the reason the server seems to crash once we have over 500 users online for a live stream, this is the main reason I wanted to setup our own server.

So my question is;

Is using the same application for the live stream, DVR stream, and file recording a recommended configuration or is there a good reason to separate the live transcoded stream and have a separate transcoded application for the DVR and Recording?

Thanks,

Kirk