Plex Media Server struggling to transcode 4K

Plex Media Server Desktops & Laptops
1

Hello Everyone,

Plex seems to struggle with 4K transcoding on my server. I am trying to pinpoint the problem so I know what steps I can take to fix the issue.

Additional Information

My Hardware:
-Dual Xeon E5 2630
-70GB of Ram
-8 x 250SSDs (2 x Raid 5 Arrays)
-Host OS - Proxmox
-Server OS - Windows Server 2K16

I followed the quide located here: https://support.plex.tv/articles/201575036-why-is-my-video-stream-buffering/

I found that my transcoder has a speed of around .8 when encoding 4K. I just want to know if I am doing something wrong or may need to check some settings. I am under the assumption that this hardware should be strong enough to transcode 4K just fine, but I could be wrong. Do I need to throw a GPU in the server? Just grasping for any answer at this point!

2

Not really sure which exact version of the CPU you got.
Your chip wonā€™t provide any hardware transcoding, so it comes all down to your CPUs. Depending on your videoā€˜s bitrate youā€™ll need a passmark (benchmark) of 8,500-15,000 to transcode 4K content (can go up to way over 17,000 for high-quality).

If you use a v2 or v3 of that Xeon, that might not be good enough:
https://www.cpu-monkey.com/en/compare_cpu-intel_xeon_e5_2630_v2-91-vs-intel_xeon_e5_2630_v4-640

Can you verify if Plex uses both of your processors?

3

To answer your questions :smile:

  1. I was mistaken about the exact processor. They are E5 2640 v2 not 2630 (not that it makes much of a difference)
  2. My passmark score when I ran it yesterday was just over 21000
  3. It is a v2
  4. How do I check this?
4

That passmark sounds about right for the two of them together 2x 8-core Xeon w/ 10k passmark each.

Regarding #4: if youā€™ve got direct access to the server, just trigger a 4K transcode and check the task manager

5

Doesnā€™t appear the Plex is using both CPUs


Row 1&2 is CPU 1
Row 3&4 is CPU 2

VM is getting 2 CPUs with 10 cores each.

6

indeedā€¦ which brings you down to approx. 10k passmark and in the middle of the shark infested water of transcoding island :frowning:

1 Like
7

I have a secondary server that has an i5-7500. Would that be better? I noticed that the i5 has 264 encode/decode so I am wondering if it might actually perform better

https://www.cpu-monkey.com/en/compare_cpu-intel_xeon_e5_2640_v2-79-vs-intel_core_i5_7500-669

8

The hardware transcoding should help.
Iā€™m running my Plex server on a low(er) power version of this CPU (i5-7500T). Never tested 4K transcoding beforeā€¦ works great when transcoding a 40Mbit/s video to playback on my tablet B)

9

I am setting up an Ubuntu VM right now! When I have results I will let you know :smiley:

11

@flow said:
https://support.plex.tv/articles/115002178853-using-hardware-accelerated-streaming/

I should have been more clear, this is running in a virtual machine. Hardware accelerated streaming is not supported on a VM in plex ā€¦

12

So I setup the Ubuntu Server VM on my secondary proxmox server running on a i5-7500. I instantly saw results! The i5 has builtin encoders and they kicked in. Verbose logging shows that I get around 1.7 on average as my encoding speed on my 4K movies!

It is odd but kinda cool that one four core i5 is better at encoding that two twelve core xeon E5s lol

Thanks for all the help @tom80H ! :smiley:

13

Sorry to revive this post four months later, but it just came up on a forum search for ā€œ7500Tā€. Iā€™m considering buying the same processor, for a computer that canā€™t handle Coffee Lake. Are you still happy with the chip? Any regrets?

14

Still happy

1 Like