HW transcoding isn’t working smoothly with Nvidia GPU

Plex Media Server Desktops & Laptops
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I’ve got plenty of 4k HDR HEVC remuxes, I know you shouldn’t transcode 4k hdr as it washes out ecc., but I would like to do that sometime. The thing is: I added a p2000 to my i5 4440, and it’s not working, it buffers every 30 second. The cpu usage is 40% but the GPU doens’t seem to like that video format and doesn’t decode that (gpu usage 10%).

What’s wrong? Everything else is being transcoded correctly, latest plex version (non beta), latest drivers, win 10 PRO.

Someone said that you CANNOT transcode a 4k HEVC with that video card since it’s a single NVENC and not powerful enough, and even software decoding with an i7 8700k would push the cpu to it’s limit.

So, basically it’s a PLEX limitation? Does anyone successfully transcode 4k HDR? What kind of setup do you have?

I don’t need many transcodes, just 1 or 2.

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I see the same result. I’ve just set the throttle buffer to 600. If the content is without too much action in the beginning it seems to have a big enough buffer to power through any action parts later. Other than that I have no solution. I’ve put adding 4K content on hold for now. I’m happy with my P2000, but if anyone had mentioned it’s shortcomings I probably wouldn’t have bought it.

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Lots of details here:

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you may also need to disable any integrated intel gpu

otherwise you probably need a monitor plugged into the p2k, or a fake monitor plug

this is not true, the quadro p2000 is the lowest gpu with the unrestricted encoder. The gtx and lower number quadro cards have limited encoders.

the limit is not plex, its nvidia’s limitation they want you to buy more expensive cards.

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While the P2000 is unrestricted in the number of concurrent sessions it can do, it will only use one instance of nvdec for each job. So it might choke on a 4K job, while at the same time run several 1080p jobs at the same time without issues.

Or can the P2000 just add nvdec sessions to one decoding job, and cruise through a 4K decoding job? If that is the case I’m not seeing it.

I think there needs to be a clearer explanation of what it meant by unrestricted. I’m certainly not getting the full effect I expected before getting the P2000.

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there are many others with working p2k.

I think you don’t quite understand how it works.

it is not the ENcoding (x264) that is hard.

it is the DEcoding (x265) that is hard.

so the limited ENcoder while certainly annoying, is not a show stopper.

we have been fine with cpu’s have been doing 1080/720 encodes for many years now.

so the important part is decoding the 4k. which should work fine in windows, but is currently not supported in linux.

there are many many threads here and elsewhere on plex and the p2000.

if your cpu is not at 100% and your stream is not buffering constantly, then most like your p2k is working fine.

on recent windows 10 versions, you can even view real time GPU load on the task manager

as for what the restrictions, you can see from the chart provided by nvidia @ https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

that all gtx cards, and all quadro cards below the p2k have encoder restricted to 2 sessions. What sessions means is not explained, but from my experience it seems to be processes. IE 2 processes + however many threads from each process.

unrestricted means there is no hard limit, and whatever limit is going to simply be the processing power of the particular card.

for non-4k transcoding you should be easily getting dozen or more transcodes without maxing the p2k, you will hit the cpu limit first.

keep in mind also, that gpu only does VIDEO transcoding, it does not do any AUDIO transcoding.

Further, with 4k transcoding the cpu also has to manage the IO of the disk and network, which is substantial and with old and/or low end cpu’s or subsystems, they simply may not have the throughput required.

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I just posted about this a few minutes ago…Im having the same issue with my P2000. It works perfectly in Emby though!! And I can do h.264 content fine in Plex…

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maybe something related to this

but it should be working on version 710

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Nope, did not fix it. I was very excited seeing those patch notes but no luck :frowning: tested it throughly with that new update.

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https://postimg.cc/jWbwGwbk

Sorry for the picture, as you can see cpu is on 35/40% while gpu is 8%, what’s wrong with that? it buffer but i can’t see what is the bottleneck that causes this.

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what does your plex server dashboard status show ?

https://app.plex.tv/desktop

status > dashboard

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That’s the exact issue this thread is about. Your Video decode decode should be closer to 30-35% usage.
Are you transcoding 4K? Is hw accel on?

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for a p2k the gpu load is not going to be very high for a single movie.

the i5 4440 is not exactly a new or powerful cpu, so the cpu load will never be as low as the gpu.

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That is incorrect. On emby(which works properly), it sits at around 30-35% and does the same on Plex for h.264 content. It doesn’t mean you can only do 3 streams before making out though. On emby I can get about 5-6 4K h265 streams at once on my p2000.

When it shows usage in the teens, that means it’s not working properly. Which was what the op was saying and experiencing and is my exact experience. I can’t play trancoded h265 smoothly. It goes at a rate of .5-.8 which is slow. On emby I get about 3.5 doing the same task.

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gotcha.

I don’t know what your both experiencing, but the gpu must be doing something because otherwise the CPU load would be maxed out trying to decode 4k x265.

they are in the middle of upgrading the transcoder, so that could very well be part of the problem.

if you need it working right away, I would suggest you go back to the last build that worked for you.

otherwise unless logs are posted and a dev or someone can review them, probably not much else we can do.

I’d still like someone to post the dashboard status while playing a problem video. If [hw] is shown for both decode/encode, then its obviously working, but not working right. Otherwise need to figure out which isn’t working and what could be causing it (other than plex itself).

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So the issue is, BOTH CPU and GPU usage is too low. It’s not playing back either. It’s transcoding WAY too slow. .5-.8 according to taut. Cpu usage is about 10-15% and gpu decode is 10-15%. And yes is says (hw) on the dashboard. If I turn off hw accel my cpu usage rockets up to 75% or so. When transcoding h264 everything functions normally.

No build of Plex( since at least August) worked.

Emby works correctly with h.265 and my p2000. That’s how I know usage is way too low.

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Exactly as mongoose above

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That’s what I’m getting as well. It might go as high as 1.8 occasionally, but most of the time it is below 1. I’m getting my info from both the dashboard and from Tautulli. I’m also running the server on a Ryzen 1700 cpu, and a nvme ssd. The 4K test content is playing from the local nvme drive. There should be no bottleneck apart from the transcoder. Nice to hear Emby is working correctly.

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well this thread has the completely wrong title, it should be something like HA transcoding isn’t working on pms version ####

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