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wisem2540

Plex 4k transcoding: New CPU or GPU offloading

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I have an older CPU.  Phenom 1045T with a passmark of about 4800.  I use Roku to play back almost all content.  I figure I have 3 options here.

 

1.  Keep server as-is and switch out the roku platform for something that can play 4k hvec natively

2.  I looked at new CPUs.  The Ryzen 2700x seems to be a good value with a reasonable 17000 passmark, thoughts?

3.  Add a GPU to handle transcoding

 

 

Option 1 would obviously be the cheapest.  But long term I am not sure this solves alot of my issues.  The server is older and the CPU keeps up with every other demand other than transcoding.

 

Option 2 is ultimately the most expensive.  The CPU alone is north of 300 dollars.  Add a board, RAM, new PSU, and probably a new h310 HBA (since im in there) and the price starts creeping up to 750 pretty quick.  That is, of course, assuming the 2700x is a good value for my application.

 

Option 3.  Doing some light reading, I understand that there may be a way to do GPU offloading for transcoding.  I can easily obtain a 1070 for $300, or even a 1070TI for just over $400.  What are people using in this space?  And how does GPU transcoding compare to CPU?

 

Thanks for all input

 

Edit:  After some more reading, it looks like option 3 may only be available on Intel-based systems?  If this is true, perhaps a combination of a server refresh with some GPU offloading makes sense?

Edited by wisem2540
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I'm using Plex and streaming to my Roku devices.

I'm having Plex create optimized versions until I upgrade my server hardware.

So it doesn't matter if it's a full blu-ray ISO, a 4k/UHD or other similar high bitrate file, I have the original and a copy that will play without issue given my current limitations (CPU isn't powerful enough for H265, or really high bitrate H264).  By the time my library has a significant 4k/uhd/h265 content, I should have already planned and at least started my rebuild that will be fully capable.

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While this may not be helpful, personally I don't find 4K worth it to be honest. Sure it looks nice but how much nicer than 1080p? I know this is subjective, many people might say it looks 100 times better and so they fell it's worth it, some people might not. I read so many threads about people literally spending hundreds of dollars to outfit their systems to play 4K and I just wonder if in the end, they feel spending the money was worth it.

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51 minutes ago, ashman70 said:

While this may not be helpful, personally I don't find 4K worth it to be honest. Sure it looks nice but how much nicer than 1080p? I know this is subjective, many people might say it looks 100 times better and so they fell it's worth it, some people might not. I read so many threads about people literally spending hundreds of dollars to outfit their systems to play 4K and I just wonder if in the end, they feel spending the money was worth it.

 

Im actually glad you brought this up.  Let me also share my reasoning for this..     When I started ny library almost 10 years ago, I always ripped my content as a 700MB Compressed DVD Rip.  I thought it looked perfectly fine on my 32 and 42in TV, especially from a distance.  As time passed and my TVs have gotten larger, my SD rips look downright awful, and I find myself scrambling to upgrade my content.

 

In response to that, I know try to capture my content in the highest resolution possible to "future proof" myself.

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Totally understand, I can't stand watching SD content either. I also have a 4K 60' tv and an Nvidia Shield, but I've compared 4K to 1080p and the difference, to me, is just not enough to justify what is required to obtain 4K content and everything else that it involves. There is a Youtube video about a guy who compares 4K retail movies to Bluray and he found out that the major studios downsample 4K to 2K anyway, so when you buy a '4K' movie, it's really only 2K anyway. Hey, to each their own is what I say, it's just not for me, I'm perfectly happy with 720p/1080p.

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Id still like to get some recommendations on whether GPU offloading is the right idea here.  If so, I could spend less on a CPU.  

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On 6/22/2018 at 10:49 AM, ashman70 said:

Totally understand, I can't stand watching SD content either. I also have a 4K 60' tv and an Nvidia Shield, but I've compared 4K to 1080p and the difference, to me, is just not enough to justify what is required to obtain 4K content and everything else that it involves. There is a Youtube video about a guy who compares 4K retail movies to Bluray and he found out that the major studios downsample 4K to 2K anyway, so when you buy a '4K' movie, it's really only 2K anyway. Hey, to each their own is what I say, it's just not for me, I'm perfectly happy with 720p/1080p.

 

On a 60" TV, they will look about the same, as you have observed. But, 4K is really meant for going above and beyond 65" into the 70, 75, 85, and 100+inch category. That may seem ridiculous to you now and "too big" but just a few years ago, the same arguments were made about 60 and 65" TVs and 1080p... people were saying, "I can't tell the difference between 720p and 1080p on my 43" TV."

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On 6/25/2018 at 1:23 PM, grooves12 said:

 

On a 60" TV, they will look about the same, as you have observed. But, 4K is really meant for going above and beyond 65" into the 70, 75, 85, and 100+inch category. That may seem ridiculous to you now and "too big" but just a few years ago, the same arguments were made about 60 and 65" TVs and 1080p... people were saying, "I can't tell the difference between 720p and 1080p on my 43" TV."

This. I've had my 65" plasma for 5yrs but haven't had a great urge to upgrade to 4k strictly because I would have to get a 75"+ for it to make sense given my viewing distance. And guess what... prices suuuuck at the 75" mark, haha. This hasn't stopped me from purchasing 4k Blu-Rays, but it slows my desire to fill up my drives with 4k content for the time being.

 

With that said, I'm also interested in the subject at hand given the direction of things. I'm having to switch to a server rack in the next 4-6mo due to maxing out my case's drive capacity, and will surely have to upgrade my hardware a year or so after that (especially to accommodate more users,) so I'm curious what the current state is in regards to GPU support.

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I have a core i3 8100 with intel UHD 630 graphics
it can transcode 10-bit HVEC 4K easily, the igpu is a beast.
so this cheap $130 cpu can easily outperform a $400 cpu with hardware acceleration
keep in mind that only the 8th generation igpus can transcode 10-bit HVEC so I recommend buying something like the 8100, i5 8400,8500 if you don't want to spend a lot of money

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I would get a GPU maybe an AMD or NVIDIA Quadro because the GTX has a two-stream limit ( there are patched drivers out there that should solve that). I use an NVIDIA Quadro P4000 mostly for plex, that's a bit overkill, but I do some CAD work where the Quadro series is a good choice.

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Does NVIDIA or GPU transcoding actually work yet on Linux/unRAID?

I thought I read somewhere that it doesn't actually work yet, or am I mistaken?

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Depend how you define work...

unRAID currently does not have drivers for NVIDIA GPUs (and it is unlikely to get them). The same applies to Radeon GPUs though i dont know if those are even useful for trans-coding. Since docker containers require drivers to be installed on the host OS, you cannot use those GPUs to do hardware trans-coding in dockerized applications on unRAID. Assuming however that your hardware supports passing a GPU through to a VM you could always run hardware accelerated trans-coding apps in a VM. Yes it is a little more resource intensive than a docker container but not a huge problem if you have a server specced for VMs. Alternatively unRAID does have drivers to support GPUs integrated in Intel CPUs.

Edited by primeval_god

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A few points about plex HW transcoding.. its buggy at best. I use it.. and I disabled it. 

 

AMD cards as of writing this, are still not 'supported'. That being said, enabling HW transcoding seems to offload 'some' work to amd gpu's.

 

Nvidia cards work, but only 1 HW transcode unless you've got a high end CAD card(non consumer/gaming), they seem to be able to handle give or take 10 transcodes. 

 

Transcoding 'is multhreaded', however it still prefers IPC over threads. A single i9 7xxx, or thread ripper still smashes even quad socket mobo setups. Same goes for gpu's. 

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@tbonedude420
Question for you then. If you were going to build primarily for 4k/UHD transcoding, would you build around CPU or GPU? (assuming plex in a docker)

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1 minute ago, whipdancer said:

@tbonedude420
Question for you then. If you were going to build primarily for 4k/UHD transcoding, would you build around CPU or GPU? (assuming plex in a docker)

Hands down CPU. i9 7960x, or threadripper v2. (or v1)

https://forums.plex.tv/t/transcoding-4k-requirements/136994

 

Realistically, your gonna spend between 1-2 grand for a 4k viable system. Be it in cpu, or gpu. Cpu can be recycled and reused.. gpu's have a quicker death and are less likely to be reused

 

Other things to note, are the container (.avi, .mkv, ect..) and the codecs used to convert (h264, x264, hevc x265, ect..)

Also, you cant pass-through a GPU to a docker, so GPU's are out of the question. Also given the pricetag of the m5000 (capable 4k gpu) you mid as well get a baller CPU. M5000 isnt even the most expensive option... some cad/rendering cards are upwords of 10 grand. 

 

In short, x264 is bigger, but easier to convert. x265 is smaller, but harder to convert. HEVC is amazing, if you can support it, but you need a pretty beefy cpu to even play, let alone transcode. 

 

Finally, if you choose to go with HEVC for example, not all clients support this, and it will have to be transcoded again to the end user.

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On 9/11/2018 at 1:36 PM, tbonedude420 said:

Hands down CPU. i9 7960x, or threadripper v2. (or v1)

https://forums.plex.tv/t/transcoding-4k-requirements/136994

 

Realistically, your gonna spend between 1-2 grand for a 4k viable system. Be it in cpu, or gpu. Cpu can be recycled and reused.. gpu's have a quicker death and are less likely to be reused

 

Other things to note, are the container (.avi, .mkv, ect..) and the codecs used to convert (h264, x264, hevc x265, ect..)

Also, you cant pass-through a GPU to a docker, so GPU's are out of the question. Also given the pricetag of the m5000 (capable 4k gpu) you mid as well get a baller CPU. M5000 isnt even the most expensive option... some cad/rendering cards are upwords of 10 grand. 

 

In short, x264 is bigger, but easier to convert. x265 is smaller, but harder to convert. HEVC is amazing, if you can support it, but you need a pretty beefy cpu to even play, let alone transcode. 

 

Finally, if you choose to go with HEVC for example, not all clients support this, and it will have to be transcoded again to the end user.


Thanks for this.

BTW, I'm planning my upgrade. You can see my current MB/CPU combo in my sig, but suffice to say I built this 7-ish years ago. I'm starting to see the age, because as my media library has expanded, Plex has slowed considerably (~3k movies & ~12k tv episodes - in a variety of encoding, ~90k songs in mp3/flac, ~5k pics/videos).

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Well, I can only state based on my experience

Emby does work fairly well as a docker with intel iGPU (Kaby-Lake, Coffee-Lake in the 6.6 series) to do accelerated transcoding. of course there's a single stream limit I think for iGPU HW decoding...

 

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Hi,

i just set up an UNRAID server as a media server including PMS in a docker container.

Hardware is an Intel i7-8700 sitting on a ASRock Z370-Extreme4-board with 24GB RAM.

I´m currently moving from FullHD to 4K-content and found as well that plex requires significant more performance for 4K than for FullHD-transcoding.

 

My current setup (described above) plays three 4K streams simultaniously without a problem. CPU load is at 30%.

Hardware transcoding is enabled in the plex docker and is used for all streams.

 

AFAIR i spend less than €500,- (~$590,-) for the board an the cpu.

 

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I have a coffee lake CPU, is there a guide you followed to get the hw transcode working? 

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