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SOLVED: Tracking/Starting Slow - Printable Version

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Tracking/Starting Slow - JellyEll - 2025-01-13

Hi All

[edits for general coherence sake]

Apologies, I've scoured the forums and although I can see problems like mine, trying the solutions either hasn't worked or I've not seem the exact same behaviour on Jellyfin/Jellyfin logs. I will throw all of the information I can here - some may be too much, I may have missed other parts. Feel free to ask for more, and thank you in advance.

When users are direct streaming OR transcoding, the time to start a film or time to scrub through the films seems to be longer than I would have expected (ranging from 12s -> 3 minutes). It does seem to be consistently slower when transcoding, but still often slow when direct streaming. Most of the time, once the stream has started, it works, but scrub forward/backwards will cause buffering again.

I'm running Jellyfin 10.10.3 on K3s (not sure how we feel about container orchestration, but I already have a bunch of services in Kubernetes, so it made sense).

The path is:

End User -> CloudFlare Proxy -> Router (900down/150up) -> Gigabit Switch -> One of the Kubernetes hosts (https://www.aliexpress.com/item/1005005234874016.html, 16Gi RAM instance) -> Gigabit Switch -> Sinology TS-653 Pro w/ WD Golds.

I'm running HW transcoding - QSV (Also tried VAAPI) using /dev/dri/renderD128. I've logged into the container and can confirm that I've passed through the hardware properly and is accessible by the running user.

I read from some other posts that if the ffmpeg command doesn't have a path after the -i switch, it isn't hw transcoding, but I'm not sure if that's accurate or not. I have configured it how I thought I read to configure it.

[Image: z52RtJS.png]

Code:
root@jellyfin-76d4d6768c-qqxj7:/# ls -lah /dev/dri/renderD128
crw-rw---- 1 root 104 226, 128 Jan 12 19:03 /dev/dri/renderD128

I've tried creating a new library using local storage (m2) and copying and playing a file to it - this doesn't seem to change the buffer time.

I've tried disabling the proxying in CloudFlare, no change there.

I've recently moved house, with new internet and new switch, that hasn't sped it up, so I'm not against it, but I'm loathe to believe it's network related.

Thes are the logs from a stream start that took 24 seconds from pressing play to having media actually play:

Code:
[16:42:44] [INF] [3] Jellyfin.Api.Helpers.MediaInfoHelper: User policy for Me. EnablePlaybackRemuxing: True EnableVideoPlaybackTranscoding: True EnableAudioPlaybackTranscoding: True
[16:42:44] [INF] [92] Jellyfin.Api.Controllers.DynamicHlsController: Current HLS implementation doesn't support non-keyframe breaks but one is requested, ignoring that request
[16:42:44] [INF] [92] MediaBrowser.MediaEncoding.Transcoding.TranscodeManager: /usr/lib/jellyfin-ffmpeg/ffmpeg -analyzeduration 200M -probesize 1G -fflags +genpts -f matroska  -i file:"/movies/The Jester (2023)/The.Jester.2023.1080p.BluRay.DDP5.1.x265.10bit-GalaxyRG265[TGx].mkv" -map_metadata -1 -map_chapters -1 -threads 0 -map 0:0 -map 0:1 -map -0:s -codec:v:0 copy -tag:v:0 hvc1 -bsf:v hevc_mp4toannexb -start_at_zero -codec:a:0 libfdk_aac -ac 6 -ab 640000 -copyts -avoid_negative_ts disabled -max_muxing_queue_size 2048 -f hls -max_delay 5000000 -hls_time 6 -hls_segment_type fmp4 -hls_fmp4_init_filename "4d56fba990b106dde8bbacde0ded367b-1.mp4" -start_number 0 -hls_segment_filename "/config/data/transcodes/4d56fba990b106dde8bbacde0ded367b%d.mp4" -hls_playlist_type vod -hls_list_size 0 -y "/config/data/transcodes/4d56fba990b106dde8bbacde0ded367b.m3u8"
[16:42:48] [INF] [16] MediaBrowser.Controller.MediaEncoding.TranscodingJob: Stopping ffmpeg process with q command for /config/data/transcodes/4d56fba990b106dde8bbacde0ded367b.m3u8
[16:42:49] [INF] [92] MediaBrowser.MediaEncoding.Transcoding.TranscodeManager: FFmpeg exited with code 0
[16:42:49] [INF] [16] Jellyfin.Api.Controllers.DynamicHlsController: Current HLS implementation doesn't support non-keyframe breaks but one is requested, ignoring that request
[16:42:49] [INF] [16] MediaBrowser.MediaEncoding.Transcoding.TranscodeManager: /usr/lib/jellyfin-ffmpeg/ffmpeg -analyzeduration 200M -probesize 1G -ss 00:51:44.851 -noaccurate_seek -fflags +genpts -f matroska  -i file:"/movies/The Jester (2023)/The.Jester.2023.1080p.BluRay.DDP5.1.x265.10bit-GalaxyRG265[TGx].mkv" -map_metadata -1 -map_chapters -1 -threads 0 -map 0:0 -map 0:1 -map -0:s -codec:v:0 copy -tag:v:0 hvc1 -bsf:v hevc_mp4toannexb -start_at_zero -codec:a:0 libfdk_aac -ac 6 -ab 640000 -copyts -avoid_negative_ts disabled -max_muxing_queue_size 2048 -f hls -max_delay 5000000 -hls_time 6 -hls_segment_type fmp4 -hls_fmp4_init_filename "4d56fba990b106dde8bbacde0ded367b-1.mp4" -start_number 516 -hls_segment_filename "/config/data/transcodes/4d56fba990b106dde8bbacde0ded367b%d.mp4" -hls_playlist_type vod -hls_list_size 0 -y "/config/data/transcodes/4d56fba990b106dde8bbacde0ded367b.m3u8"
[16:43:00] [INF] [100] MediaBrowser.MediaEncoding.Transcoding.TranscodeManager: Transcoding kill timer stopped for JobId b14a2a04e07d43bb90b42037a654885c PlaySessionId c95282ff2dc74216a118f16bce5c1bc3. Killing transcoding
[16:43:00] [INF] [100] MediaBrowser.Controller.MediaEncoding.TranscodingJob: Stopping ffmpeg process with q command for /config/data/transcodes/ca4dc911ca8351a6dd6d09ac33a07bb6.m3u8
[16:43:00] [INF] [100] MediaBrowser.MediaEncoding.Transcoding.TranscodeManager: FFmpeg exited with code 0
[16:43:00] [INF] [100] MediaBrowser.MediaEncoding.Transcoding.TranscodeManager: Deleting partial stream file(s) /config/data/transcodes/ca4dc911ca8351a6dd6d09ac33a07bb6.m3u8
[16:43:06] [INF] [16] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.

This is all with just one user at a time and I see you wonderful people running a lot more on a lot less hardware, so I'm clearly missing something.

Any ideas on where my configuration is wrong, or how to tune would be hugely appreciated. Thank you for reading through!

RE: Tracking/Starting Slow - bitmap - 2025-01-13

Any idea exactly which processor you have? The Synology site only says Intel Celeron 2.0 GHz and the only matching quad-core CPU I could find was a J1900. Looking at the Intel QSV support, the Celeron processors in the Haswell generation are not particularly capable and explicitly do not support HEVC at all. So what's happening is that folks are starting media playback and your older machine is decoding and encoding the media on the CPU without any hardware acceleration.

See: https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video#:~:text=Fixed%2Dfunction%20Quick%20Sync%20Video%20format%20support

ETA: If you provide your ffmpeg logs via pastebin, we can take a look (Dashboard > Logs and look for ffmpeg in the log name). I would guess it's transcoding *extremely* slowly.

RE: Tracking/Starting Slow - TheDreadPirate - 2025-01-13

You should disable proxying in Cloudflare. It is against their TOS to serve video/audio through their free tier proxy service.

Additionally, you problem could be caused by this proxying.

RE: Tracking/Starting Slow - JellyEll - 2025-01-13

I've disabled this as a performance thing to test and it didn't work - should have read the TOS better, so I'll disable it for that sake permanently, thank you.

RE: Tracking/Starting Slow - JellyEll - 2025-01-13

(2025-01-13, 05:23 PM)bitmap Wrote: Any idea exactly which processor you have? The Synology site only says Intel Celeron 2.0 GHz and the only matching quad-core CPU I could find was a J1900. Looking at the Intel QSV support, the Celeron processors in the Haswell generation are not particularly capable and explicitly do not support HEVC at all. So what's happening is that folks are starting media playback and your older machine is decoding and encoding the media on the CPU without any hardware acceleration.

See: https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video#:~:text=Fixed%2Dfunction%20Quick%20Sync%20Video%20format%20support

ETA: If you provide your ffmpeg logs via pastebin, we can take a look (Dashboard > Logs and look for ffmpeg in the log name). I would guess it's transcoding *extremely* slowly.


The Application host has an n100 CPU:
Code:
Vendor ID:                GenuineIntel
  Model name:            Intel(R) N100
    CPU family:          6
    Model:                190
    Thread(s) per core:  1
    Core(s) per socket:  4
    Socket(s):            1
    Stepping:            0
    CPU(s) scaling MHz:  34%
    CPU max MHz:          3400.0000
    CPU min MHz:          700.0000
    BogoMIPS:            1612.80

Is the NAS important for transcoding? I thought it was done on the application host (those Firebats)? The NAS is just pure storage. You're right, though, it has a Celeron J1900 Quad Core.

A couple of pastebins - thanks so much for helping out

FFMPEG.TRANSCODE: https://pastebin.com/MVu1KL98
FFMPEG.DIRECTSTREAM: https://pastebin.com/7tTbaaKf

RE: Tracking/Starting Slow - TheDreadPirate - 2025-01-13

Why are you using VAAPI instead of QSV?

RE: Tracking/Starting Slow - bitmap - 2025-01-13

(2025-01-13, 06:26 PM)JellyEll Wrote: The Application host has an n100 CPU:
Is the NAS important for transcoding? I thought it was done on the application host (those Firebats)? The NAS is just pure storage. You're right, though, it has a Celeron J1900 Quad Core.

You are 100% correct, that is my bad. TDP has the right question -- you may see an increase in performance swapping over.

RE: Tracking/Starting Slow - JellyEll - 2025-01-13

Honestly, I’ve been using QSV the whole time, I just tried VAAPI today to see if that would improve anything. I didn’t notice any performance change for better or worse.
Did you want me to test again with QSV, for the sake of getting better logs?

RE: Tracking/Starting Slow - bitmap - 2025-01-13

Give it a shot and see what happens. Might lead down the road to a solution.

RE: Tracking/Starting Slow - TheDreadPirate - 2025-01-13

Switch to QSV and share the ffmpeg log from that.

I also noticed it is burning in the subtitles, which occurs partially on the CPU. Did you restrict the number of cores that container could use?