Plex/Proxmox/Debian Hardware Transcoding

[bporourke2]

Server Version#: 1.41.5.9522
Player Version#:
<If providing server logs please do NOT turn on verbose logging, only debug logging should be enabled>

Hello all,

I have a proxmox server set up with an lxc running plex. I have a nvidia 3060 that I want to use for HW acceleration. Plex is using the gpu for encoding, but not decoding. I have all of the nvidia drivers/cuda/nvidia-smi etc passed from the host. When I review the logs, it shows that it is using the gpu for encoding, but when I check nvidia-smi it shows no utilization which is strange.

How can I get gpu decoding working? I have attached my logs, I just turned off verbose before starting a recent transcode
Plex Media Server Logs_2025-03-20_22-37-19.zip (1.1 MB)
so these logs may potentially have some verbose entries so please accept my apoogies!

[ChuckPa]

I’m not a proxmox expert or even regular user but have a working LXC which does HW transcoding.

The container was setup using the TTECK helper scripts

GitHub - tteck/Proxmox: Proxmox VE Helper-Scripts

You should be able to tune it to your needs.

[bporourke2]

That’s actually what I started with, maybe I’ll try rebuilding the container from scratch with that

[ChuckPa]

Here’s what it shows. Hopefully that helps

let me know what you need and how to get it.
I’ll gladly share

[bporourke2]

it appears the bundled ffmpeg doesnt have support for HEVC sources to be used with nvidia hardware. Does that seem correct? I do have HEVC enabled in my setting on plex

[ChuckPa]

Yes, the FFMPEG bundled with PMS does support HEVC sources and encoding.

You MUST have hardware to support the HEVC encoding.
There is no software HEVC encoder.

I have a P2200 and RTX2000, HEVC has been supported for a long time (decoding) and HEVC encoding was recently added.

In transcoder Advanced settings, did you explicitly select the Nvidia (by name) ?

Are you passing the Nvidia runtimes into the LXC ?

I add /dev/dri and then the runtime

# Add it (Both Intel and Nvidia)
lxc config device add "$1" GPUs gpu gid=$Gid

# Add Nvidia runtime 
lxc config set "$1" nvidia.driver.capabilities all
lxc config set "$1" nvidia.require.cuda true
lxc config set "$1" nvidia.runtime true

[bporourke2]

I can see the card from the lxc when I run nvidia-smi, and I think I have all the settings enabled in plex. Thats why I am leaning towards a plex issue rather than proxmox issue.

the logs indicate it is using nvenc for encoding but doesnt use nvdec for decoding