Jellyfin hardware transcoding in a Proxmox LXC with Intel iGPU: the config that finally work

Problem: when my parents watch something on the phone, Jellyfin transcode on CPU and the i5-8500T go to 95%, fans loud, and everything else on that node become slow. The iGPU (UHD 630) was sitting there doing nothing. It took me 2 evenings to make Quick Sync work inside an unprivileged LXC, so here is everything.

1. Check the host

ls -l /dev/dri
crw-rw---- 1 root video  226,   0 ... card0
crw-rw---- 1 root render 226, 128 ... renderD128

renderD128 is what we need. Major number 226.

2. Pass it into the container

On Proxmox 8.2 and newer it is one line in /etc/pve/lxc/105.conf (105 is my Jellyfin container):

dev0: /dev/dri/renderD128,gid=104

The gid must be the render group inside the container. Check with getent group render inside. Mine is 104, yours can be different.

On older Proxmox the old way:

lxc.cgroup2.devices.allow: c 226:0 rwm
lxc.cgroup2.devices.allow: c 226:128 rwm
lxc.mount.entry: /dev/dri dev/dri none bind,optional,create=dir

With the old way in an unprivileged container you also fight with uid/gid mapping. The dev0 line save you from that, upgrade if you can.

3. Inside the container

usermod -aG render jellyfin
apt install intel-media-va-driver-non-free   # needs non-free in sources
/usr/lib/jellyfin-ffmpeg/vainfo --display drm --device /dev/dri/renderD128

vainfo must print "Intel iHD driver" and a list of profiles (H264, HEVC Main, HEVC Main10...). If it say permission denied, go back to the gid.

4. Jellyfin settings

Dashboard, Playback, Transcoding:

• Hardware acceleration: Intel QuickSync (QSV)
• Enable hardware decoding for: H264, HEVC, HEVC 10bit, VP9. Not AV1, 8th gen cannot decode AV1
• Enable hardware encoding: yes
• Low power encoding: I leave OFF. On 8th gen it needs GuC/HuC firmware enabled on the host kernel, not worth the drama for me
• Tone mapping: on, if you have HDR files

5. Check it really work

On the host install intel-gpu-tools and run intel_gpu_top while you play something that need transcode. The "Video" engine must be busy. If the CPU still go 95%, something fall back to software, check the Jellyfin ffmpeg log for that playback.

Result

• One 1080p HEVC 10-bit to H264 stream: CPU 95% → 8%
• 4 streams at once: iGPU ~30%, CPU ~20%
• Power at the wall during transcode: from ~45W to ~19W on that node

hope this help :)