General bandwidth questions

[DeanoVIP]

Hi, sorry novice question but I've been experiencing some stutters in game on a different machine on my network and discovered it's my Jellyfin server being the culprit.  The stutters occurs every minute for or so, when a single TV is streaming from the server.

My home network is 300 down and. 50 upload, and all WiFi based due to no way to run ethernet.  This has never been an issue the whole house has good coverage.

So I figured I would try and limit the upload speed on the Jellyfin server for streaming playback.  I've set it to 18mbps, is that enough for two TVs to stream 1080p?  The server uses a 6th i5, I have transcoding selected too if that's correct (believe it's supported by this generation processor).  Is that set high enough, and are there any other settings worth changing?

Secondly the app on my Chromecast has this button next to the crop button which ranges from auto/ 140mbits down to 1mbits, what is this for?  Image attached for reference.

[TheDreadPirate]

That is for selecting the max allowed bit rate. This does NOT change the bit rate of a video if the video is LOWER than that setting. If you select a bit rate that IS lower than the video's bit rate your server will transcode the video to meet that lower bit rate selection.

We'd need to see your jellyfin and, if applicable, ffmpeg logs. And what OS are the two TVs running? Android TV? Roku?

[DeanoVIP]

Thanks for the reply, so assuming I selected a lower bit rate than the video and the server transcodes, I would be saving on upload bandwidth at the sacrifice of the server (CPU) doing more work? I'll attach some logs/configs next time im logged in. I know I use quicksync for most options selected apart from 10bit hevc IRC.

I run two Rokus and a Chromecast just on dumb tvs that are 1080p. The main time I notice this is on the chromecast. I assumed it buffered so much and then had to buffer another chunk and at the point is where I see the latency and packet loss when trying to play a game for around 5 seconds at a time.

[DeanoVIP]

Hi Pirate,

I've attached some more screenshots of the settings, apologies if there is anything better I can provide please let me know.  Also a log file (there will be an error around 22:30 'ish' I rebooted the server while something was streaming.

[TheDreadPirate]

If the two TVs are NOT on the same network, you should aim to keep your total upload usage to about half your available bandwidth. Which would be 12.5Mbps if, max, you have two remote clients streaming.

If they are local clients, your Internet bandwidth doesn't matter.

[DeanoVIP]

Thank you all devices are local in the house, and all on the 192.168.0 subnet. So could the streaming just be the cause of a top much over the WiFi on the Lan? Apologies this may be reaching outside of Jellyfin now. So that bandwidth limit on playback - streaming only applies to the outside world streaming?

[TheDreadPirate]

The settings on the SERVER for stream bit rate limits are for remote connections not on the same LAN. The bit rate settings on the CLIENT are separate and aren't really useful for local clients. Though, there is a bug where the auto setting doesn't detect the bandwidth correctly and sometimes transcodes unnecessarily so just set it to the max 120Mbps.