Advice on PC Build for Plex Virtual Machine host

Plex Media Server Desktops & Laptops
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I recently consolidated my computers to VM’s. My VM host is running ESXI 6.5 on Intel NUC 5i5yRU w/16Gb RAM and 2TB HDD. The Plex Media Server is running on a dedicated VM running Centos 7 with 4 CPU’s and 3GB RAM. The CPU pegs when transcoding. I though about turning down settings and quality, but I decided that I want to have the features so I need to upgrade.

The CPU pegs when transcoding ( screenshot attached ). The Plex VM is called Dionyus in these pictures.

Requirements:

  • Be compatible with VMWare ESXI 6.5
  • Be able to hosting 8 VM’s
  • Run super quiet since I’m in a 1BR apartment, the server will be about 14 feet from where I watch television/play video games. Silence is a must!
  • Handle 1-2 simultaneous transcoding streams for Plex
  • Dual nics or slot for nic card
  • Upgradable CPU/Memory in case my requirements increase
  • No gaming, it will only run server apps.

The host has VM’s running things like ELK stack , Chef, Plex Media Server, LAMP, Nagios etc for studying, software development, and home entertainment.

**Here is my current build idea parts list with prices from Amazon.com:
**CPU: **Intel Core i5-6500 3.2GHz Quad-Core Processor **$153.88 . - would a Xeon be better?
Motherboard: ASRock - H270M-ITX/ac Mini ITX LGA1151 Motherboard $92 . - I like the dual intel nics on this
Memory: Corsair - Vengeance LPX 32GB (2 x 16GB) DDR4-2133 Memory $259.88
Case: Fractal Design - Node 304 Mini ITX Tower Case $119.99 - quiet and well built
Power Supply: EVGA - SuperNOVA GS 550W 80+ Gold Certified Fully-Modular ATX Power Supply $83.88
Total: ~$690.63
Note - I’ll use hard drives and ssd card that I have lying around for storage. I have a separate NAS that stores my media files.

I’d like to get the community’s thoughts on price and parts selection ? I’ve read that Xeon CPU’s are better since I won’t be playing games on this system.

1 Like
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I changed things up a bit to use a server motherboard and Xeon E3-1230 v5 processor. Build is here ->

pcpartpicker.com/user/PCPartkomrad/saved/BCVqsY

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@TheGooch

first… the cpu will always peg for a bit when you start a transcode. it plex can multiplex the transcode it will 90%+ all cpus for a period until it throttles. If the transcode is single thread bound (VC1 codec for example) you will see one core spike to 90%+ and likely stay there unless your processor has a passmark (single thread) about 1200ish … then it will be lower the better it is.

so your choice of a e3-1230V5 has a single core passmark north of 2000 so you should be good even for worst case…

now that is if plex was running bare metal… esxi has its own specifics…

you only have a single 4 core cpu capable of 8 threads… if you are running other VMs and you give plex 4 cores… it will take over your CPU every time its scheduled to do work… esxi can only schedule the VM if there are available cores equal to or greater than the number scheduled in the VM… so you will get cpu contention… it may run better if you give it 2 vCPU depending on how many other VMs your running and how many simul transcodes you are trying to get out of your box.

For my setup… I went with dual L5640 and 48G memory… that gets me 12 cores/24 threads and each thread is VC1 capable.

and it cost a whopping $300 bucks… dual intel nics, and most important… the cpu and motherboard are both on ESXI approved hardware list… which means the drivers have been tested against the hardware and qualified.

you should be ok with your setup if you dont have too many VMs running at the same time with 2+ vCPU … if you find CPU wait starting to spike you will need to read up on cpu scheduling and contention and either size you vCPU better or get into a system with more threads/memory.

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Here is the parts list for others who are looking for the same setup:

  • CPU: Intel - Xeon E3-1230 V5 3.4GHz Quad-Core Processor
  • Motherboard: ASRock - E3C236D2I Mini ITX LGA1151 Motherboard ($239.99 @ Newegg)
  • Memory: G.Skill - Ripjaws V Series 32GB (2 x 16GB) DDR4-2133 Memory ($240.99 @ Newegg)
  • Case: Fractal Design - Node 304 Mini ITX Tower Case ($99.98 @ Newegg)
  • Power Supply: Corsair - CSM 550W 80+ Gold Certified Semi-Modular ATX Power Supply ($69.99 @ Newegg)

Total: $675.94
Generated by PCPartPicker 2017-08-20 15:35 EDT-0400
PCPartPicker part list: https://pcpartpicker.com/list/R8v96X
Price breakdown by merchant: https://pcpartpicker.com/list/R8v96X/by_merchant/

5

@dragonmel said:
@TheGooch

first… the cpu will always peg for a bit when you start a transcode. it plex can multiplex the transcode it will 90%+ all cpus for a period until it throttles. If the transcode is single thread bound (VC1 codec for example) you will see one core spike to 90%+ and likely stay there unless your processor has a passmark (single thread) about 1200ish … then it will be lower the better it is.

so your choice of a e3-1230V5 has a single core passmark north of 2000 so you should be good even for worst case…

now that is if plex was running bare metal… esxi has its own specifics…

you only have a single 4 core cpu capable of 8 threads… if you are running other VMs and you give plex 4 cores… it will take over your CPU every time its scheduled to do work… esxi can only schedule the VM if there are available cores equal to or greater than the number scheduled in the VM… so you will get cpu contention… it may run better if you give it 2 vCPU depending on how many other VMs your running and how many simul transcodes you are trying to get out of your box.

For my setup… I went with dual L5640 and 48G memory… that gets me 12 cores/24 threads and each thread is VC1 capable.

and it cost a whopping $300 bucks… dual intel nics, and most important… the cpu and motherboard are both on ESXI approved hardware list… which means the drivers have been tested against the hardware and qualified.

you should be ok with your setup if you dont have too many VMs running at the same time with 2+ vCPU … if you find CPU wait starting to spike you will need to read up on cpu scheduling and contention and either size you vCPU better or get into a system with more threads/memory.

Those are good insights. The message “server is not fast enough to transcode this stream” ( paraphrased ) is what prompted me to investigate . Videos were also intermittently locking up , going in an unending “waiting” look an that little circle that rotates clockwise. I started watching the CPU memory graph in ESXI web console and running the. “top” resource monitor on the virtual machine running PMS.

Adding more sockets to the VM made it’s performance in “top” look better, but at the ESXI host level things still looked bad. Since I still have a few more VM’s to add( eg Docker host, Nagios server, and more ) , I decided it was a good time to give my system more headroom by upgrading.

It was tough choice between making a really small , quiet, good-looking server that could do the job and saving money on a lower cost large, noisy, and power hungry solution such as a Dell 710/r720 blade server, TS140, HP T7500 , etc , but I decided to spend more and get something closer to my dream box. With some more cash I would have gone with a Supermicro board and dual Xeon’s , but I can always do that later if I need to.

2 Likes
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Update,- I just bumped the cores for the Plex VM from 2 to 4. Since it was pegging the 3GB of RAM I gave it during transcoding, I bumped it up to 8GB .

It’s running well, but I do regret my choice in CPU’s after reading up on Plex’s hardware acceleration setting in the “transcode” section. It uses the Intel Quick Video Sync (QVS) feature which Xeon E3-1230 processors don’t have. I might swap out motherboards and get a CPU that supports QVS to future proof it.