High Cpu usage while transcoding

High Cpu usage while transcoding - Printable Version

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High Cpu usage while transcoding - Tux - 2024-10-26

Hi,
current situation is as following when i try to wathc a UHD move/show e.g. "House of the Dragon", which cant be direct played on a device (e.g. tablet/smartphone) I get a cpu usage of 95%-100% which obviously indicates that the gpu is not used.

So my setup, as of now:
OS: Ubuntu 24.04
Kernel: 6.8.0-47-generic
CPU: intel 12100
Jellyfin runs in a docker container and is started via systemd
within the following config

Code:
[Unit]

Description=Jellyfin Service

After=docker.service

Requires=docker.service

[Service]

TimeoutStartSec=0

Restart=always

ExecStart=/usr/bin/docker run --name jellyfin --rm --publish 8096:8096 --user 1000:1000 --volume /home/stefan/jellyfin/config:/config --volume /home/stefan/jellyfin/cache:/cache --device=/dev/dri:/dev/dri --device /dev/dri/ --group-add 110 --mount type=bind,source=/media/stefan/mediastorage4/MEDIA,target=/media jellyfin/jellyfin:latest

[Install]

WantedBy=default.target

group 110 = render
with jellyfin user is part of render group

Code:
stefan@mediaserver:/etc/systemd/system$ getent group render

render:x:110:jellyfin,stefan

if i start a stream and check with "intel-gpu-top" I can see the gpu doesnt render and it basically transcodes 100% via the cpu
here is a log from jellyfintranscode https://pastebin.com/NTgPmY6m

If someone could help my why the igpu is not utilized this would be great.
Also if some information is missing let me know
Thx in advance

RE: High Cpu usage while transcoding - Fate - 2024-10-26

That is weird your transcode log shows it is transcoding via GPU
Stream #0:0 -> #0:0 (hevc (native) -> h264 (h264_qsv))
Stream #0:4 -> #0:1 (ac3 (native) -> aac (libfdk_aac))
You should be at least see some usage on intel_gpu_top.

But it is also audio transcoding which is a CPU-only task.

Can you take a few screenshots of the Transcoding section so see what is selected there?

RE: High Cpu usage while transcoding - nyanmisaka - 2024-10-26

The hardware decoder is not enabled.

RE: High Cpu usage while transcoding - Tux - 2024-10-26

(2024-10-26, 12:18 PM)Fate Wrote: That is weird your transcode log shows it is transcoding via GPU
Stream #0:0 -> #0:0 (hevc (native) -> h264 (h264_qsv))
Stream #0:4 -> #0:1 (ac3 (native) -> aac (libfdk_aac))
You should be at least see some usage on intel_gpu_top.

But it is also audio transcoding which is a CPU-only task.

Can you take a few screenshots of the Transcoding section so see what is selected there?

pictures attached

Nvm thx, I just saw there is a settings for "HEVC" and "HEVC 10 bit"

Thx, i didnt know there is a option for "HEVC" and "HEVC 10 bit", while transcoding seems to work now, cpu usage is at ~ 15% and intel_gpu_top is busy rendering. It is still struggling to keep a fluent stream. At least gpu transcoding seems to work now,
EDIT: quality setting was at 4k/120mbps LOL, guess this is too much to transcode, switching to 1080p/60mbps seems to work just fine.

Thx