Plex Server Chokes on 4K Video

Spaceninja

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I have an older machine I am running for my Plex sever. It is a Core i5 650 with 8 Gig of ram running Ubuntu Server. I can play back 1080 video just fine to my Roku boxes, one is an Ultra and the other is a 4K. I know the Roku isn't the issue as they are the current higher end models. Is the CPU really a bottleneck for this? The machine doesn't do anything else.

Is it time to put this old machine out to pasture and replace it with something a little newer?
 
I have an older machine I am running for my Plex sever. It is a Core i5 650 with 8 Gig of ram running Ubuntu Server. I can play back 1080 video just fine to my Roku boxes, one is an Ultra and the other is a 4K. I know the Roku isn't the issue as they are the current higher end models. Is the CPU really a bottleneck for this? The machine doesn't do anything else.

Is it time to put this old machine out to pasture and replace it with something a little newer?

I use an older laptop (b950 chip) to stream 4k. It used to have buffering issues when I had 6gb of ram, but increasing it to 8gb fixed the issue. Are you able to upgrade the memory at all?
 
I think it has 2 more slots for ram. I'd have to take it down off of the wall, and take the top off to see if it does. I'm sure I can come up with a few more sticks to upgrade it to 16. All of the 4k content is on the local drive in the server. The other 720/1080 content is on a NAS. I moved it to make sure that network lag wasn't an issue.
 
Look at Task Manager and see if the CPU is pegged or the Ram is at 100%.
I am guessing it has to transcode and the CPU is maxed out.
 
Doesn't appear to be maxing out, but cpu is hitting about 85%. I was wondering if anyone had used one of the 6 or 8 core AMD Fx chips for Plex. I figure they will start dropping in price soon.
 
I have an older 8 core FX-8150 Black for my Plex server but I only stream up to 720p content, don't really feel the need for 1080p or higher, and I only use a pair of Apple TV4's and those aren't 4K.

I got a deal on the chip and an Asus Sabertooth 990FX board, $60 for the pair.

IMG_0943.JPG
 
What is the 4k content encoded with? X265 is extremely cpu intensive.
 
if the 4k source is encoded properly with x265 (hevc) it should just direct play on your roku and require very little work by the server.

check your plex settings on your roku and make sure you have the local quality set to original. ignore the "not recommended" blurb.

otherwise, your plex server will be transcoding down to the lower bitrate which taxes the cpu heavily.
 

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I made the changes but I still get some stutter in the stream. It'll buffer about every 5 minutes or so. I don't think it is a bandwith issue as I have a Netgear Nighthawk AC1900 router. The server is connected via cat5 to the router then the Roku's are wireless. The one in the living room is about 3 feet away on the other side of a wall.
 
I made the changes but I still get some stutter in the stream. It'll buffer about every 5 minutes or so. I don't think it is a bandwith issue as I have a Netgear Nighthawk AC1900 router. The server is connected via cat5 to the router then the Roku's are wireless. The one in the living room is about 3 feet away on the other side of a wall.

my roku ultra is hardwired. i tried out the wireless and i also get buffering. my router is about 10 feet away in the same room.
 
x265? It hurts the CPU.
My i5-6600 struggles with transcoding a 720p x265 for my FireTV.
Actually, struggle is an understatement.
It's simply unwatchable.
 
I don't have to watch 4k stuff. it looks nice, but still yet. I might look into one of the 8 core FX boards and procs. I can't justify building a new Ryzen rig, unless I shuffle some machines around.
 
I don't have to watch 4k stuff. it looks nice, but still yet. I might look into one of the 8 core FX boards and procs. I can't justify building a new Ryzen rig, unless I shuffle some machines around.


Or just stop transcoding it. My 60 dollar apollo lake can play 10bit 4K with ease from my NAS. Just delete plex.
 
Or just stop transcoding it. My 60 dollar apollo lake can play 10bit 4K with ease from my NAS. Just delete plex.

If it were just me I would. Plex makes it easy for the kids to find episodes of shows and movies they want to watch.
 
8 Core FX chip here. 9590 (traded my 8370 for one) I can transcode 4k plex just fine.
The Plex container only has 8GBs allocated to it as well
 
x265? It hurts the CPU.
My i5-6600 struggles with transcoding a 720p x265 for my FireTV.
Actually, struggle is an understatement.
It's simply unwatchable.
Odd, because the i5-760 in my plex box can transcode 1080p HEVC down to ~3Mbit 720p without any stuttering. Granted it pegs all four cores at like 90-95% or so...
 
Odd, because the i5-760 in my plex box can transcode 1080p HEVC down to ~3Mbit 720p without any stuttering. Granted it pegs all four cores at like 90-95% or so...

8 but it 10bit. Big diff
 
Yea, I have found that 4k streaming isnt exactly smooth, its ok unless i try to rewind or forward or sometimes even pausing.

That was with plex and serviio, so I guess most streaming apps probably suffer from some freezing and or buffering whilst streaming 4k content, thats just my experience.

i7 6700k 32gig ram and streaming over cat6.
 
But plex isn't streaming, it's transcoding right?

What does it transcode this too?
 
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Why do people still transcode stuff?


Is this 2007?

very few devices support 4k x265, even then it has to been in a very specific format, otherwise it transcodes to 1080p. I transcode to remote devices because my upload is only 8mbps
 
x265 is going to tax your CPU with Plex whether you are transcoding to a lower bitrate or not. On my system below, with a high bitrate 1080P x265 file, it'll max the CPU out for a solid 10 minutes at least. Eventually the CPU calms down. This is direct streaming straight to a Roku Ultra over Cat6. This has been posted all over Plex forums. I have one high bitrate 4k HEVC x265 file and damn if my CPU doesn't stay maxed out during the entire playback. I don't get stuttering. Plex simply isn't that optimized for HEVC codecs yet.

Now, I have found that I can use my TV's DLNA browser and watch the same files with a noticeably reduced CPU hit on my PC. *shrug* So, it is Plex causing the CPU to spike.
 
very few devices support 4k x265, even then it has to been in a very specific format, otherwise it transcodes to 1080p. I transcode to remote devices because my upload is only 8mbps

You'd be surprised. The problem with 4k HEVC stuff, is there's no real legal source of getting it. Of course the real advantage of having some would be WCG and HDR... which transcoding would break, not to mention ruin your perfectly encoded source :(.
 
Can you test it with a hardwired roku? I think it still might be a wireless issue.
 
Can you test it with a hardwired roku? I think it still might be a wireless issue.

I had to end up running ethernet to my Rokus, I have a 1900AC router and great wifi but it still wouldn't stream stuff off my NAS. I think it's the Rokus, I can stream off the NAS to a wifi PC without any problem, but the Rokus (they are the newish Roku 3s, not the 4K Roku 4) would buffer frequently.
 
Roku 3 only has 802.11n, not that great

LOL, I didn't realize the 3 was already a discontinued product, looks like even the 4 is no longer current. But at least I now have ethernet everyplace I have a Roku, so I got that going for me - as long as they don't drop the ethernet port.
 
LOL, I didn't realize the 3 was already a discontinued product, looks like even the 4 is no longer current. But at least I now have ethernet everyplace I have a Roku, so I got that going for me - as long as they don't drop the ethernet port.

Wired will be a better choice but 802.11n is more than fast enough ..its probably the Roku itself causing the issue
 
Wired will be a better choice but 802.11n is more than fast enough ..its probably the Roku itself causing the issue

Not really, the 3 is probably limited to 1x1 150mbps, that's theoretical speed, real world would be about 70mbps, and if it's 2.4GHz lucky to get 20-25mbps, closer to 10-15mbps.

EDIT: Roku 3(either version) doesn't even support 4K, so it'll force plex to transcode no matter what to 1080p

EDIT 2: No Roku has gigabit Ethernet, yuck
 
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Not really, the 3 is probably limited to 1x1 150mbps, that's theoretical speed, real world would be about 70mbps, and if it's 2.4GHz lucky to get 20-25mbps, closer to 10-15mbps.



LOL, lets be honest, you pulled those numbers out of your ass. I can easily hit 90 mbps on my Roku , and all that is really needed for the highest quality is about 12 .

anyway, OP can add the speed test channel and run his own test..


https://www.rokuguide.com/private-channels/speed-test
 
Not really, I deal with wifi daily, with service ranging from 1.5mbps dsl to gigabit fiber. Different modem and routers etc etc. each situation is different. There could be hidden interference from something, neighbors wifi who knows. I posted those numbers based on my experience with each type of wifi. I don't know your network, or which Roku you have. So one persons situation can't apply to everybody

EDIT: the speed test is only from ISP to Roku, not actually the connection between Roku and router
 
LOL, lets be honest, you pulled those numbers out of your ass. I can easily hit 90 mbps on my Roku

Agreed, I regularly hit ~100-110Mbits/sec transferring data from my phone to my desktop over 11n. (access point is only 1x1 capable, not sure about the phone)
 
Not really, the 3 is probably limited to 1x1 150mbps, that's theoretical speed, real world would be about 70mbps, and if it's 2.4GHz lucky to get 20-25mbps, closer to 10-15mbps.

EDIT: Roku 3(either version) doesn't even support 4K, so it'll force plex to transcode no matter what to 1080p

EDIT 2: No Roku has gigabit Ethernet, yuck

Probably because there isn't really anything yet to justify needing more than 100mbps on the wired port. There is only theoretical 108mbps on 4k bluray but in actuality nothing really reaches that yet. We might see it in the next Roku but until now they were better served putting the budget into faster wifi to overcome the difficulties there. You pretty much need AC to stream 4k, you don't need gigabit to stream 4k.
 
Probably because there isn't really anything yet to justify needing more than 100mbps on the wired port. There is only theoretical 108mbps on 4k bluray but in actuality nothing really reaches that yet. We might see it in the next Roku but until now they were better served putting the budget into faster wifi to overcome the difficulties there. You pretty much need AC to stream 4k, you don't need gigabit to stream 4k.

If you are transcoding 4k and want it to look decent, it needs to be well over 100mbit.
 
Plex Media Server automatically detects the resolution of your screen and draws the interface accordingly. The app also supports playback of 4K video files using the H.264 (AVC) codec in most containers, so long as your computer is powerful enough to decode it.
 
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