PLEX 4k playback AND transcoding lag


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Alright I could use some help identifying a bottleneck in my system.

 

Problem:

I can't play back a 4k (HEVC Main 10 HDR w/ TRUEHD 7.1) movie from my unRAID server to my new (Roku Enabled 4k TCL) TV either directly OR via transcoding without significant buffering / lag.

 

Important info and specs:

1. unRAID server and TV are connected via a local lan running 1gbps direct wired CAT6 

2. Using PLEX with GPU Transcoding via a Nvidia Quadro P2000 - should be capable of multiple 4k stream transcoding 

3. Server CPU is E3-1246 v3 @ 3.5GHz and 32GB ECC RAM. 

 

I really have no idea where to begin debugging the direct playback buffering issue. The TV plays great for several minutes then either buffers or says the connection to server was not sufficient. During direct playback, the server CPUs stay low and appear just fine - but I still have buffering! The PLEX datarate shows this is using ~89mbps to stream which my network should do no problemo. Possibly an issue with the TV not being able to handle the TRUEHD 7.1 audio???

 

Now for transcoding - system appears to be using the GPU properly but maybe is trying to use the CPU for audio transcoding and failing there? If I try to transcode a 4k movie at all, all CPU spikes to basically 100% and I get buffering on the TV even though I bought a $300 GPU to prevent this. Running "watch nvidia-smi" shows the GPU being used for the transcoding as shown below.  What gives here?

 

Here are screenshots of transcoding from thr 4k down to 720p (4mpbs😞

 

htop.thumb.PNG.6128aed4557195a666538c995f594fea.PNG

 

nvisiasmi.PNG.17de0edff17a17a56a8fb55c9167d303.PNG

 

plex.PNG.b0d22638941a810349cc1be1642765fd.PNG

 

unRAIDGUI.PNG.f182c89cbb9e756d965906b7e95e45bb.PNG

 

Thanks for the help!

 

 

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holy shit! Man you totally just solved all my problems! I had no idea 4k was the devil! I'll just delete it immediately, return my 4k tv, and go pick up a 1080p model at goodwill asap! /s

 

I'm so sorry to come off as mean in this response. I really am. This is honestly a pet peeve of mine and you kinda triggered me hardcore - I'm just SOOOO tired of posting to forums about technical topics only to be told "Don't do what you're trying to do" for some reason. It's just not a productive or valid answer in the modern world of ever advancing technology. It's just an excuse. A cop out. 

 

In fact, I have seen this post you reference - just not in detail because it turned me off of itself immediately. STOP saying 4k is evil and don't do it. It's truly like saying drugs are the devil and don't do any of them. How about explaining the REASON WHY!!!! (based on my data posted.) and the technical paths forward. 4k is the goddamn future whether it's ready on a specific platform or not. 

 

I do now see several relevant topics in the post you reference. This is a complex technical problem and my entire post is centered around understanding the specific faults in my system for 4k streaming and transcoding - I need help with this because it's hard. 

 

1. Is the Audio the source of my lag? The article references DTS and notes about manually removing certain audio formats. I this applicable based on the content I'm trying to play as referenced in my original post?

 

2. What's the best way to currently separate libraries for 4k content vs 1080p content in plex? Any good guides / tutorials on doing so? I reallly hate to have to do this, but if it's the only technical solution, be it. 

 

3. 4k is the future. What are the missing links for plex/emby/unRAID. What still needs to be done / or is in progress to make 4k streaming and transcoding easy?

 

Anyway. ranting aside - If your're going to reply, how about instead, you provide an explanation relevant to the data I listed in the original post as to what is the root of the problem. 

 

 

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4 hours ago, iamatesla said:

holy shit! Man you totally just solved all my problems! I had no idea 4k was the devil! I'll just delete it immediately, return my 4k tv, and go pick up a 1080p model at goodwill asap! /s

 

I'm so sorry to come off as mean in this response. I really am. This is honestly a pet peeve of mine and you kinda triggered me hardcore - I'm just SOOOO tired of posting to forums about technical topics only to be told "Don't do what you're trying to do" for some reason. It's just not a productive or valid answer in the modern world of ever advancing technology. It's just an excuse. A cop out. 

 

In fact, I have seen this post you reference - just not in detail because it turned me off of itself immediately. STOP saying 4k is evil and don't do it. It's truly like saying drugs are the devil and don't do any of them. How about explaining the REASON WHY!!!! (based on my data posted.) and the technical paths forward. 4k is the goddamn future whether it's ready on a specific platform or not. 

 

I do now see several relevant topics in the post you reference. This is a complex technical problem and my entire post is centered around understanding the specific faults in my system for 4k streaming and transcoding - I need help with this because it's hard. 

 

1. Is the Audio the source of my lag? The article references DTS and notes about manually removing certain audio formats. I this applicable based on the content I'm trying to play as referenced in my original post?

 

2. What's the best way to currently separate libraries for 4k content vs 1080p content in plex? Any good guides / tutorials on doing so? I reallly hate to have to do this, but if it's the only technical solution, be it. 

 

3. 4k is the future. What are the missing links for plex/emby/unRAID. What still needs to be done / or is in progress to make 4k streaming and transcoding easy?

 

Anyway. ranting aside - If your're going to reply, how about instead, you provide an explanation relevant to the data I listed in the original post as to what is the root of the problem. 

 

 

I don't have the experience to help you (I went the easy path and got a nvidia shield so no 4k transcoding needed), but if you want someone to spend their own time to actually help you, I'd edit that response and take out all the whining.

  • Like 1
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I echo the previous comment. Be civil, polite and tone down any antagonism. It's not polite, and this IS  a very polite forum as I hope you agree, and unwanted. Ask a straighforward question in plain English and see what help can be offered if it's help you are actually after and not just shouting for shoutings sake. Be prepared for a minimal response. It could be hard to take but I've found that asking nicely in a civil manner normally gets results.

  • Like 2
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i cant help you with the problem, i just going to show that it can work fine.

4K Plex / Unraid, Direct play. no buffering or what so ever, just fine. yes, transcode 4K, is a pain in the ass (just don't do that)

i don't have a GPU free for Plex (the 2 a have are occupied bij Unraid gui and the desktop VM) so no hardware acceleration.

 

Just test play 2 4k movies on the same time, Unraid/Plex show that it just fine (78Mbps / 81Mbps) even with subtitles enabled.

1 stream to TV and the other on de desktop (with PlexMediaPlayer)

 

i do have a smartTV but don't use the smart functions, instead i hooked a Vero4K (kodi/OSMC box) on it.

(the TV phones to much to home and the user agreement sucks)

and like a already say, transcoding 4k sucks, so its only working fine local.

 

 

plex4kdirectplay2.jpg

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