Hardware for 4K Streaming

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dstnzrjkl

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Quick backstory: So I was able to get a good amount of unused server hardware from a friend that was purchased for business use then never actually used and he wanted to offload at a very reasonable price so here's what I have.
  • SUPERMICRO MBD-X10SRH-CLN4F-O
  • Intel Xeon E5-2620 V4
  • Crucial 16GB (2 x 8GB) 288-Pin DDR4 SDRAM ECC DDR4 2133
  • SAMSUNG 960 EVO M.2 250GB NVMe
  • 3 x HGST Deskstar NAS 3.5" 10TB 7200 RPM 256MB
I'm about halfway through backing up all my Blurays and have gotten a few 4K's now as well. I'm ripping full quality remuxes for everything and I'm likely adding a few more drives and some more of the same RAM soon.

My player of choice was Roku Ultra as it seemed to have the most compatibility and best media center interface for others to use but I don't think Roku has anything to do with my issue.

If subtitles are used, it forces it to transcode and really no matter what quality it buffers every minute or so which makes it unwatchable. Also most 4K that I've tried watching will also buffer every 5-10 minutes but just for a few seconds, but that ruins the immersion for sure.

Now I can't see what's going on here to cause this. I thought for sure this would be more than enough hardware to easily transcode a single 4K stream if absolutely necessary which it doesn't even have to do, all it does depending on the movie is transcode some audio but still direct play the video.

Watching CPU usage via htop shows very little usage regularly and only ~10-20% during 4K transcoding if I turn on subtitles. But then it'll buffer every minute or so.

Network shouldn't be an issue either, both the server and Roku are wired into the same Ubiquiti Switch, I've been able to pull 1Gbps to and from the server so it should be fine on that end.

Any help or suggestions would be greatly appreciated.

Thanks.
 

Nick2253

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How are your drives configured? Do you have Plex installed via the plugin, a custom jail, or via a VM? How have you tested the transfer speed? Have you tested full video files? Have you tested the cabling from the switch to the Roku?

Have you tested this with other clients? Based on your server, I find it difficult to believe that your server is the limited factor.
 

dstnzrjkl

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Drives configured? I'll I'll assuming you mean plugged in and filesystem. They're all just using the onboard SATA ports as the original case I had didn't quite fit my media rack and the one I downgraded to no longer had a SAS backplane for hotswappable drives so just went with SATA and had FreeNAS manage everything. And using ZFS for filesystem.

Plex is installed via a plugin which I'm considering changing as to be able to manually update without causing issues.

As far as speed goes I've just transferred files to and from the server via SMB from a windows machine on the network pretty much maxing out my Gigabit.

A movie I was testing last night has a bitrate of 80Mbps, I'd assume that would be no issue at all. I've been able to fully saturate my ISP at 500Mbps, actually a little extra pulling about 56MBps.

Not really sure the best way to test the Roku's speed to try and max out the line, but I've tested the cable itself on the Roku with a laptop and again get full speed into the same port the Roku is plugged into.

Tested with Apple TV as well but that's all for streaming locally on the network.

I agree the server shouldn't have any issue. I was going for overkill here, not wanting to worry about having to upgrade for quite some time.

I did just try the whole testing pool speed with the 'dd' command, and looks like it's only pulling about 157 MB/s for a 20GB file for both reading and writing.

I currently only have 3 drives but just ordered 3 more as I'm nearing 80%.
 

Nick2253

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Drives configured? I'll I'll assuming you mean plugged in and filesystem. They're all just using the onboard SATA ports as the original case I had didn't quite fit my media rack and the one I downgraded to no longer had a SAS backplane for hotswappable drives so just went with SATA and had FreeNAS manage everything. And using ZFS for filesystem
RAIDZ1? Mirrors?
 

Nick2253

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Tested with Apple TV as well but that's all for streaming locally on the network.
So, did you have the problem with the Apple TV? So far, I haven't seen any indication that this isn't a Roku problem. Everything else seems to work just fine.
 

dstnzrjkl

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Oh yeah that makes sense. RAIDZ1

And yes Apple TV also had the issue.

Apple TV has it even worse because it doesn't support Direct Play for just about any 4K remuxes, so no matter what that's going to get transcoded which gives issues every minute or so. About that same as turning on Subtitles which also causes trancoding of the video.
 

garm

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I don’t think you have either the RAM or the CPU horsepower to deal with 80+ Mbps streams and ZFS at the same time.

If you google your problem you see recommendations of 16000 passmark scores for single 4K streams. My present home lab server has plenty of RAM and a score of just north of 7000 passmark and it cannot deal with 4K content.
 

Nick2253

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If you google your problem you see recommendations of 16000 passmark scores for single 4K streams. My present home lab server has plenty of RAM and a score of just north of 7000 passmark and it cannot deal with 4K content.
That seems ridiculous. My desktop's i7-2700k can handle a 4k transcode without issue, and its passmark is half of what you're proposing is required. If @dstnzrjkl were CPU limited, I imagine he would be seeing more than 10-20% CPU usage. Plex is multithreaded for pretty much everything.

However, one of the important single threaded exceptions for Plex is VC-1 media, which is typically used for 1:1 bluray rips. @dstnzrjkl, what format is your media?
 

dstnzrjkl

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Just about everything is HEVC or H.265 whatever you want to call it, and I only get the 10-20% usage when I force it to transcode by burning in subtitles or playing on Apple TV as it doesn't support Direct Play and trancodes all 4K to H264. When playing regularly through Roku it's at like 1-3% depending on other processes.
 

Bhoot

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Figure out what the requirements for 1080p transcoding is, then work from there. As per the specs Plex has released, transcoding 1080p 8Mbps takes about 2K passmarks on the CPU per stream. And since a 4K stream is roughly 4x the bitrates, that means you need roughly 4x the passmark score for every stream you intend to have transcoded.

As you can see, this ramps up quite quickly.

So asking for an affordable CPU and 4K in the same question is almost an oxymoron. There isn't anything really "affordable" when talking 4K transcoding.

OTOH, if you can ensure that it 's only going to Direct Play, then the passmark requirements aren't there. And almost any CPU capable of supporting PMS can be used. As there aren't a lot of devices with H265 supported natively (In the client apps, that is) choosing the right HW and client app is just that much more important.

Here are the guidelines. Any deviation will most likely cause transcoding of 4K. Neither you and I put together could prolly afford a CPU fast enough to do any meaningful transcoding of 4K. (An Aside, Why have 4K media just to transcode it anyway. Makes 0 sense to do that)

Follow this
Container = mp4
Video Codec = h.265
Audio Codec = AC3 2 channel or 5.1

NEVER use subtitles.
 

Nick2253

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This might help: http://forums.plex.tv/discussion/299093/buffering-but-why-connection-is-fast-enough

So asking for an affordable CPU and 4K in the same question is almost an oxymoron. There isn't anything really "affordable" when talking 4K transcoding.
OP's CPU is a v4 E5 Xeon, with a Passmark well over the 8k you suggest is required for transcoding a 4k stream. A long-ago, yesteryear i7-2600k meets that requirement. An X5660 will also barely do it (and it can be purchased for $50 on eBay). 8k is hardly anything any more. Pretty much any E3 Xeon will meet that requirement.

NEVER use subtitles.
You ask why anyone would have 4k media just to transcode it anyway. This is exactly the reason. I don't have a 4k TV, but I regularly transcode 1080p streams for subtitles, especially because I love foreign films, and I go back and forth with watching them with/without subtitles as a way to improve my language skills and listening comprehension.
 

Bhoot

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My calculations are based on estimates and perfect scenarios. Would I use an 8k CPU for 4k (strictly) transcoding? NEVER. I would want to atleast double that and then add a few 1000 extra for overheads and hence my ideal CPU isn't affordable (atleast not for me). The subs are a personal choice, and I can live without it. For everyone the expectations and requirement of Plex is unique, hence an "umbrella" solution isn't possible. The early adopters do have to go out in the dark and show the light for everyone else. Since 4k technology isn't so widespread and most of the BluRays are just upscaled versions of 2k I don't see the shift of masses happening very soon.
Personally I use a Rpi3 running Rasplex and my displays are 1080p. Is it a perfect solution? Not at all. The HEVC has the green screen artefacting at every dark scene @1080p. There are few SBC which claim to decode 4k on their own I would be very weary in switching since even a platform as wide as Raspberry still trying to iron out issues.
One thing though which I would like to mention is that my files (HEVC/1080p/10bit) play without stutter which I have seen a lot of people not being able to achieve. I guess a few processors are better made than others? The passmark on the CPU are just under 6k and I haven't overclocked anything (RPi3 included). I have set the transcoder settings to automatic and more often than not I see my intel fan whine like a jet engine under load of 2 streams (1080p/HEVC/10bit). Am I happy with that? No, not really. Would I downgrade to 720p to give the CPU more breaths? No, not ever.
So like you can see a 6k processor which is 3x what plex recommends isn't the best solution either. With 2 simultaneous streams I do get mails as such
Code:
> sonewconn: pcb 0xfffff80362460498: Listen queue overflow: 151 already in queue awaiting acceptance (4 occurrences)
> sonewconn: pcb 0xfffff80362460498: Listen queue overflow: 151 already in queue awaiting acceptance (6 occurrences)
> pid 15529 (Plex Media Scanner), uid 972: exited on signal 8
> pid 15596 (Plex Media Scanner), uid 972: exited on signal 8
> sonewconn: pcb 0xfffff80362460498: Listen queue overflow: 151 already in queue awaiting acceptance (2 occurrences)

It really doesn't affect the performance and such tests are more of a synthetic load for benchmark purposes but yes, they do happen.

So take it howsoever one must but these are hard facts.

messages with uid 972 can be ignored as they are a (probable) bug.
 

Nick2253

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So take it howsoever one must but these are hard facts.
You really haven't provided any hard facts, just speculation and anecdote. You admit as much in your first sentence.

And you continue to move the goalposts on your CPU recommendation. Plex's recommendations are simple: 2k passmark as a general rule for a 10Mbps stream (a typical 1080p stream). When you look at Plex's actual CPU recommendations, they explicitly recommend a ~1500 Passmark CPU for a single 1080p stream. It's clear that the general rule is imprecise, and factors like number of cores, clockspeed, and pipeline will impact that number. They even make a specific recommendation to allow for additional overhead for client OS or other tasks. However, nowhere do they recommend doubling that Passmark recommendation, much less adding an additional stream's worth of capacity and then some on top of doubling it.

The subs are a personal choice, and I can live without it.
Congratulations?

This thread isn't about you or your preferences. It's about @dstnzrjkl's issues, and how we can fix them. Since I'm assuming this comment is in response to my earlier comments about subtitles, my point is that you cannot simply make a blanket conclusion about how people should use software. You made absolute statements about how the software should be used, and feign incredulity about any other use case. Obviously, you get that no one use works for everyone, because you say nearly as much here. Which all makes me wonder why you made those claims in the first place.

So like you can see a 6k processor which is 3x what plex recommends isn't the best solution either.
I'm not sure how you reach this conclusion. Based on your anecdote, everything seems to be working just fine. Your only complain is the noise from the stock heatsink fan, and who knows how you have your CPU fan profile configured, or what kind of temperature/airflow you have in your case, to bring us to this point. But I'm at a loss how a noisy fan does not a good processor make.

It really doesn't affect the performance and such tests are more of a synthetic load for benchmark purposes but yes, they do happen.
Listen queue overflow errors are almost always misconfigured software. There's a whole bunch of recommendations about how to troubleshoot and fix these issues. A search for "listen queue overflow" on Google will bring you right up to many of those resources.
 

dstnzrjkl

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NEVER use subtitles.

So I agree I don't want to Transcode at all, that's the idea of going with the Roku as it seemed to have the best support for direct play.

But we do have someone who joins us from time to time enjoying movies who doesn't have the best hearing so subtitles are sometimes a requirement.

Again I don't think it's a hardware limitation because it's not even attempting to use the CPU really at all. I've seen on an older system transcoding 1080p and you definitely see a hit, this isn't even making a noticeable hit to the CPU.
 

Bhoot

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I think you mistook me to be someone who works for plex. I assure you I am not employed with any of the computer giants. I'm just a man happy with his server. None of the comments are meant to be telling someone how things have to be done. Honestly picking on someone I don't even know is not my style. Yes my points are based on estimates and speculations because I can't put in hard earned money to build another FreeNAS box and buy a 4k TV just to give you my results. I told you my setup my preferences and my settings. You like it use it, you want to build a computer that competes with "VULCAN"? By all means go for it.
 

Bhoot

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I think you mistook me to be someone who works for plex. I assure you I am not employed with any of the computer giants. I'm just a man happy with his server. None of the comments are meant to be telling someone how things have to be done. Honestly picking on someone I don't even know is not my style. Yes my points are based on estimates and speculations because I can't put in hard earned money to build another FreeNAS box and buy a 4k TV just to give you my results. I told you my setup my preferences and my settings. You like it use it, you want to build a computer that competes with "VULCAN"? By all means go for it.
 
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