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liverepeater-edge/liverepeater-edge-lowlatency internal 4 seconds latency?

Hey all!!

Trying to widdle down latency between servers in an origin edge configuration and wondering if there’s anything we can do there. It seems that if we use either liverepeater-edge or liverepeater-edge-lowlatency we still see the same amount of latency off of the edge application. It looks as though it’s consistently about 4 seconds (not including client buffer).

For example, if we have the client buffer set to 2 seconds and we try re-streaming from an origin on a liverepeater-edge application, an additional 4 seconds is added, bringing the total latency to 6 seconds. I understand that this is internal and probably quite important, but is there any setting anywhere which we can easily tune that 4 second number down a bit?

Thanks!! :o)

Hi Benny,

Are you testing with a single client or multiple clients at the same time?

With a liverepeater-edge the first client triggers the edge server to request the stream from the origin as it’s not permanently connected.

The edge doesn’t request the stream from the origin when no clients are connected to the edge in an attempt to save bandwidth between edge and origin.

If you’re testing with multiple clients using the same stream (so one is always playing) this will avoid the edge needing to retrieve the stream.

Another test would be to configure an origin application and an edge application on the same Wowza server to remove any delay added by the network.

Regards,

Jason

Hey Jason!

Thanks for the reply, man…

Well, one or multiple clients play the same stream from the edge, it really depends on the situation. We’ve also been testing with an origin and edge application on the same server and not seeing any difference with that 4 second add-on to the repeating stream. So to reiterate, even if we have the origin/edge apps configured on the same server and we connect to a repeated stream with a buffer of 2 seconds on the client, the stream is 6 seconds latent consistently. And connecting to a different edge application on another server we still see that added on 4 second value. Any insight on that? :slight_smile:

Hi,

The frame rate and keyframe interval can make a difference with RTMP streams as clients require either 2 keyframes or 60 frames “I think” so this could be on the Wowza side as well as the player side.

If you’re not fussed about the bandwidth usage between the origin and edge you could try using PushPublishing to send the streams from the origin to the edge to see if this is any different.

This method means that all streams on the edges are published as would be the case using a RTMP based encoder. The edge applications will have a StreamType of “live” like the application on the origin.

Regards,

Jason