Hi all,
I’ve been running my PMS on a mid 2007 Core 2 Duo 1.83 mac mini with Windows 7 (32bit) and 3GB ram - it’s not up to the task anymore! LOL
Anyhow, I’ve been trying to work out what exactly I need to look for for a new server. Along with PMS, I run various other background apps - nothing major but thought it worth mentioning…I was originally thinking of getting an Nvidia Shield but realised I needed a PC for the background apps anyhow and I don’t want to run a PC and the Shield.
So far I’ve been pretty sure of what I need - I know I need a CPU benchmark of 2000 for a 1080p single transcode for example.
However, I’m unsure if I need to look at an i5 or if an i3 could cut it under certain scenarios (like multiple streams, some direct some transcoding etc).
So, I suddenly had an idea but not sure if it’s possible.
Is it possible to set up a virtual PC where I can specify a set configuration of the CPU and RAM?? I can then replicate what I need and test it.
FYI - I have a fairly high-spec laptop I can use to host (intel Core i7, 8GB RAM + SSD) running windows 10.
Any ideas? I’d just like the idea of doing a bit of a load test on some theoretical configurations before making any real purchases as money is a bit of a limiting factor.
Cheers,
Wayne
I still run my primary server ( and have since 2008) on an old core duo
E8400 dual core no hyperthreading and it can cut one 1080 transcode … but barely. It has to be the only app taking cpu resources
I have a test platform running on my replacement server using VMs on a dual l5640 hex server (24 threads) and experimenting with right sizing compute on the plex VM
Here are some considerations…
Number of concurrent worst case streams…
1080
4k?
Hevc to 264
Etc
One gotcha here is that on mutilcore systems … watch individual core passmark as VC1 for example is single thread
So if for instance you have a i3 or some other lowly chip that has more than a 2k passmark but each core can only push say 1k passmark… it wont be able to do a streaming realtime 1080p VC1 transcode…
This is one reason why I am virulizing plex… 99% of the time it sits idle but when the evening comes if there are multiple transcodes it can easily consume a large amount of compute…
You really just have to crunch the numbers and settle with what you are willing to pay for
I also have the source file like a mkv full blu file and a ATV3 preset h264 file for each movie so I can direct play without transode to my clients … which takes no compute … run out of network bandwidth long before it pressures the cpu
As discussed in many many threads before:
- HEVC media require 3-5 times more processing power (VC-1 is only slightly less problematic)
- ‘burning in’ bitmap subtitles (PGS, VOBSUB) require also much more processing power
- High-bitrate files, (even in H.264) require more processing power than the 2000 passmark points in this help article
So, you should keep that in mind and prepare your files accordingly:
- Avoid HEVC and VC-1 encoded files
- only use text-based (SRT, TX3G) subtitles
- if you store full BluRay rips (bitrate up to~35mbps) be prepared to have ~4000 passmark points available per transcoded stream (the additional load from bitmap subtitles and VC-1 codec not taken into account!)
Generally: If you have a choice between several cpu models, do look them up at http://www.cpubenchmark.net/cpu_list.php
Do not only look at the overall benchmark number, but also at the ‘single thread rating’. This is crucial for Plex transcoding.
When you have to choose between models with similar overall passmark score, pick the one with the highest ‘single thread rating’.
Don’t compare the performance of a desktop cpu to that of ‘mobile’ cpu’s (as built into laptops).
Also, there are i7 and i7 cpu’s 
Again: always look up the particular type of cpu (model number and clock rate).
There are a lot of Xeon cpu’s in use for Plex server which are not really suited for the task. They have a high passmark, but ‘single thread ratings’ of around 1000 points. Those cpu’s suck when used with VC-1 encoded files or when using bitmap subtitles.
This i7 cpu on the other hand, handles 2 parallel full Bluray rips with bitmap subtitles quite well:
@OttoKerner
great post as always… here is some devils advocacy though… more for plex to chew on than you or I
avoid HVEC and VC1
Well you cant avoid HEVC if you want 4k native and you cant avoid VC1 if you want straight blu ray rips as these are the native formats
plex and the encoder/decoder open source that they use as the engines in thier products need to be improved and client hardware needs to come along as well which is out of everyones hands
for example my pi wont do hardware HEVC above 720 and no vc1 support at all. Licenses are available for DTS and some other codecs if I want to be bothered.
subtitiles… this is a royal pain and to be honest I dont use then and dont want them because of all the issues… all I usually to is at riptime if I am not keeping the source material in an mkv… I will encode with handbrake and force burn in all forced foreign subs so they are in the main picture and not a sidestream… otherwise unless you are handycapt I really dont know why people want subtitles… but that is just me…
the original souce material DOENT need the 2000 passmark if all your clients can play native and you have the network bandwidth… only IF you must transcode at some point… but yes… for most… the long pole in the tent is transcode of blu… my e8400 can keep up with one stream at its a passmark of ~3000 or so… but with newer multithread cpu’s… the big gotcha is the VC1 2000+ passmark PER CORE… that snags alot of i3 and even i5 chips I believe…
