Plex not using Nvidia GPU for transcoding

[IonutZ]

Just migrated from TrueNAS Core with the hopes that I would be able to passthrough a GeForce 730 to the Plex application.

App is Plex Express 1.28.2.6151_1.7.20 from original chart on TrueNAS-SCALE-22.02.3.

nvidia-smi output below would appear as though the GPU is recognized.

In Plex's App settings, I see the following:

In Plex settings I have selected Hardware Transcoding

Whenever I run any video that requires transcoding, I see the CPU spike, and I run nvidia-smi a few times to monitor GPU temperature / memory usage and they always stay the same.

Any ideas on what I'm doing wrong? Thanks in advance!

 

[HoneyBadger]

The GT730 came in two variants - the GF108 "Fermi" based cards, and the GK208 "Kepler" - the former has no NVENC support, the latter has limited support. I suspect you might have the former.

Can you dump the output of lspci | grep NVIDIA and dmesg | grep NVIDIA?

 

[duderuud]

In Plex's App settings, I see the following:

In my instance of Scale the setting is 1 instead of 0...can you change it to 1?

 

[crkinard]

There isn't a 730 on the list at all.

Video Encode and Decode Support Matrix

Find the related video encoding and decoding support for all NVIDIA GPU products.

developer.nvidia.com

 

[IonutZ]

The GT730 came in two variants - the GF108 "Fermi" based cards, and the GK208 "Kepler" - the former has no NVENC support, the latter has limited support. I suspect you might have the former.

Can you dump the output of lspci | grep NVIDIA and dmesg | grep NVIDIA?

So I had a 1080ti laying around and figured, why not try that.... same behavior as the 730. When transcoding, CPU spikes, but 0 mem usage on GPU as per nvidia-smi and temp isn't hiking either so clearly it's not being used.

In my instance of Scale the setting is 1 instead of 0...can you change it to 1?

I'm pretty sure that doesn't represent "number of GPUs" but rather which slot GPU can be passed through... I'm running Scale virtualized inside of ESXi - so if you're running on a dedicated machine, maybe 0 for you is the onboard GPU and 1 might be dedicated, in my case I only have the passthrough GPU from ESXi recognized as the GeForce.

EDIT: Also noticed the following:

And GeForce 1080ti was under Isolated GPUs in System Settings -> Advanced. I unticked it from there, but did not notice any behavior changes.

 

[whodat]

App is Plex Express 1.28.2.6151_1.7.20 from original chart on TrueNAS-SCALE-22.02.3.

I don't see an App named 'Plex Express' in the 'Official Charts' repo... I am using 'plex 1.29.0.6244_1.7.21' '1.7.21(Healthy)' on TrueNAS-SCALE-22.02.4

I initially tried using my old GTX-760 but worked out the hard way that it is unsupported:

Jira

ixsystems.atlassian.net

(it's also not listed via the NVIDIA Decode and Encode GPU Support Matrix that @crkinard linked above)

I am now using a GTX-1660 sucessfully instead.

The GPU is not isolated in WebGUI > System Settings > Advanced.

I'm pretty sure that doesn't represent "number of GPUs" but rather which slot GPU can be passed through... I'm running Scale virtualized inside of ESXi - so if you're running on a dedicated machine, maybe 0 for you is the onboard GPU and 1 might be dedicated, in my case I only have the passthrough GPU from ESXi recognized as the GeForce.

Hmm I think this might be where you've gone astray. @duderuud was correct to suggest the GPU needs to be allocated (i.e. 1) in the Plex App settings. It's not related to the slot that is being passed through.

In the Plex App settings, I have allocated the GPU like so:

FYI I also see the same error as you from systemctl status systemd-modules-load.service :
Failed to find module 'nvidia-drm'

 

[kiler129]

I'm pretty sure that doesn't represent "number of GPUs" but rather which slot GPU can be passed through...

I think it does represent the number of GPUs to allocate as I have many apps with 0 and only plex with 1. I only have one GPU with no vGPU support in my system.

 

[whodat]

I think it does represent the number of GPUs to allocate

Yes, the WebGUI's help prompt confirms this:

 

[mjflower]

I have exactly the same issue. How was this resolved if it was?

 

[Shiggitay]

I recently installed TrueNAS Scale, and I love it... I'm also seeing that the nvidia-drm module isn't being loaded for whatever reason... Is there a fix? On the commandline/shell I did an apt-get upgrade to see what pkgs it'd attempt to upgrade, and I saw some Nvidia driver updates... How safe is that to do?

 

[SudoAdminRoot]

Does somebody found the solution for this? I don't know when but my perfectly working PLEX stopped using GPU transcode and tries it via CPU (nope, it's not PlexPASS issue...). Haven't change any settings, I did only updates.

 

[Smiakail]

I saw a YouTube video by craft computing basically explaining that truenas is only compatible with intel cpu integrated GPU.

If you are using Nvidia, you will need to create a virtual machine and install plex and Nvidia drivers on the VM to be able to use the Nvidia card for transcoding.

I also understood that in this case, you will need two gpu's. One for the system and one for transcoding (I could be wrong in my understanding)

 

[jgreco]

I saw a YouTube video by craft computing basically explaining that truenas is only compatible with intel cpu integrated GPU.

Craft computing, as usual, is full of it. As can easily be found via some searching, lots of people use a GPU along with SCALE and Plex in Docker or TrueCharts.

If you are using Nvidia, you will need to create a virtual machine and install plex and Nvidia drivers on the VM to be able to use the Nvidia card for transcoding.

Not true. You can certainly do that, but you don't need to.

I also understood that in this case, you will need two gpu's. One for the system and one for transcoding (I could be wrong in my understanding)

You're wrong in your understanding. You might WANT two GPU's. If you want to have a VGA display and you're using a crappy consumer, desktop, or workstation mainboard that lacks internal display support, it might seem like you need a GPU for that. You might, because lots of those crappy boards won't boot without a video console of some sort. If you instead buy one of the recommended server oriented mainboards, they'll include a VGA adapter as part of the IPMI, and you won't need a GPU for video. This is basically the sort of damage you can inflict on yourself when you listen to YouTube videos by people trying to monetize your eyeballs rather than people who want to provide useful and accurate information.

 

[Smiakail]

Craft computing, as usual, is full of it. As can easily be found via some searching, lots of people use a GPU along with SCALE and Plex in Docker or TrueCharts.



Not true. You can certainly do that, but you don't need to.



You're wrong in your understanding. You might WANT two GPU's. If you want to have a VGA display and you're using a crappy consumer, desktop, or workstation mainboard that lacks internal display support, it might seem like you need a GPU for that. You might, because lots of those crappy boards won't boot without a video console of some sort. If you instead buy one of the recommended server oriented mainboards, they'll include a VGA adapter as part of the IPMI, and you won't need a GPU for video. This is basically the sort of damage you can inflict on yourself when you listen to YouTube videos by people trying to monetize your eyeballs rather than people who want to provide useful and accurate information.

Thank you for clarifying all these comments.

My current setup is Trunas scale, with intel i5-11400 CPU and Nvidia Quadro P400 GPU and Plex pass. If I understand correctly, I can setup within the Trunas plex offical app the transcoding. And no extra hardware or software is required