PlexPass and Transcoding performance?

Plex Media Server NAS & Devices
1

Hi Community!

I have just purchased WD MyPassport Wireless Pro 4TB, upgraded the firmware, and deployed the PLEX server on it. What can I say… initial excitement is gradually transforming into dispair… I discovered that no so many formats are “native” to the PlexPlayer I use on my iOS devices, so it tends to transcode video stream “on-the-fly”, and naturally lacks performance due to weak CPU powerhorse…

At least, I thought so. But recent examination of this topic pushes up more questions! I hope some of you may know the answers and share thoughts?

So…

  1. The CPU used in WD MPWP is this one https://blog.minipcdb.com/realtek-rtd1195
  2. As you can see, it includes 2 Cortex A7 cores, and MALI-400 GPU with 4 cores, and what is most important, has a dedicated transcoding DSP which can transcode many formats live!
  3. PLEX Server may use or may not use multi-threading depending on the format; t.ex, it does not use it with VC-1, and I could not find any other data.
  4. When speaking of the desktop PLEX server deployments, the developers encourage user to buy PlexPath to enable GPU transcoding. That means that PLEX server core in fact, is capable of doing GPU accelerated transcoding.
  5. Thus, they reserved a very important capacity for privileged customers who pay. And they advertised this paid function and so we know for sure it will work.
  6. What about our little beast of WD? It has 2 cores, GPU with 4 cores and a dedicated DSP! It is not that weak as I thought initially! The question is, if this capacity also reserved for the priveledged customers OR there is simply NO capacity, i.e. they are not willing to implement it (for example, to sell more expensive equipment with such the capacity available)?

In other words,

QUESTION: If I buy the PlexPath, will it increase my transcoding speed and improve overall streaming performance?

I am not keen of any additional functionality the PlexPath offers, but I will gladly become a privileged customer, if it can transcode well!

Tech detail: currently it takes hours to transcode the source video at modest 480p / 2 Mbps into 4 mbps compatible 480p video (doubles the size!) at “Ultrafast” codec Settings! It looks like no hardware is used at all for the video optimization feature! Maybe, it even does not use multi threading and does all the processing on a single A7 cortex core…

What a disaster… they advertised up to 8 simultaneous streams at up to 8 mbps each ))))) hahaha…

Please share your thoughts and add comments!
Thank you everybody!

Alya

2

Update:

In PLEX media server /codecs folder I have found quite a few codec for marvel-arm7 architecture:

decoders:

AAC, AC3, DCA, h264, MP3, mpeg2video, mpeg4, mpeg4v3, wmav2

and even fewer encoders:

AAC, x264

While the question remains: why the PLEX Server for WD implementation does not support many newer formats natively supported by the processors like h265 and many others, and does it use hardware DSP of this processor to improve performance,

another question arises:

If it has mpeg2/mpeg4 support, WHY then Plex Server is always transcoding MPEG2/MPEG4 videos to x264 rather than playing them back directly???!!!

Anybody?

3

Update 2:

Also liblibhevc_encoder/decoder are missing, rendering WD MyPassport Wireless Pro essentially a “h.264/AAC” Box.

Summary: a very good potentially device with proper modern hardware (just look on the specs and DSP real-time transcoding capabilities!)

But,

A very poor implementation, lots of restrictions, only one format is fully supported, not really useful for anything but the most standardized scenarios.

Now question is: is that a marketing decision to restrict functionality and make a room for the higher models of WD, or just example of poor coding and there is a hope that things may improve in the Future?

I would gladly buy a perpetual license immediately, if there were missing codecs support (hevc), mpeg 2/4/4.3 direct play capabilities, and proper utilization of Mali GPU/ onboard transcoding DSP horsepower.

But the unit “as-is” is a poor performer. For the money it costs you’d better buy a tablet with Intel Proc, with comparable storage cost but an order of magnitude more powerful transcoding and wide formats support.

Do you think I am right or not?) Sincerely Guys)

4

It’s likely not marketing.
It’s development decision. Plex is a reasonably small development team.
Devs usually stick to most common chipsets due to time and support constrants.

Plex has limited hardware acceleration support.
That article linked even mentions 2 WD devices do not need Plexpass.
I don’t see your server device mentioned.

Plex will only download codecs on an as needed basis.
If the server performance is deemed not powerful enough for playback, it’s possible Plex doesn’t download the codec.

In the Plex ecosystem, the server is meant to be the conversion workhorse.
If you play on devices that can’t direct play your content, Plex server tries to do the work. If it can’t, due to low CPU, then Plex likely isn’t for you.

5

Hi, Jaminn! Thank you for Your answers, looks reasonable what you say, but…

Have you looked the link with the processor specs? It is definitely NOT a weak chip, with DSP to live-transcode the newest formats, even HEVC. So the only reason this box is a poor performer in terms of speed is not having this implemented, but why?))

Then, regarding playing back MPEG2/4: surely my iOS client can handle playing back the formats, as it can playback h264 which consumes much more CPU; and when I use another app on my iPhone/iPad, rather than iOS Plex client, I can directly stream/ playback MPEG2/4 with no issues. Even Twonky can translate these formats. But for some reason, not PLEX on the WD MyPassport Pro!

So I understand in the beginning of the playback there is negotiation between client and server about which format player can handle and which formats the server can translate. As the result of this negotiation the decision is made by engine which format to use. If this was a smart engine it could analyze this situation (having source in MPEG2/4 and not h264, the player request h264 because it provides better bandwidth utilization, but there is a lot of bandwidth available and live transcoding to h264 is not a good option with a weak CPU and poor coding that does not support hardware properly, so the decision engine would then decide to translate directly the MPEG2/4)

So you see, the decision making module is not smart enough to understand a simple collision and cannot trade bandwidth to CPU load, because it is not designed to!

Meanwhile more simple apps use Twonky and negotiate pretty well in this situation.

Summary: PLEX team should either implement a proper hardware support, or provide this support as a part of PLEXPASS for a fair price. If PLEX does not want to make money, they could at least write a better decision engine… converting terrabytes of videos to h264 just to suite the Plex way of thinking… really guys?))

Anyway, great thanks for sharing your thoughts!

More discussion from users are welcome!

6

This Plex article was written for you.
It even goes so far as to specifically state “Note: ARM models generally do not support video transcoding at all.”
https://support.plex.tv/articles/201373793-is-plex-media-server-on-a-nas-right-for-me/

IPhone/IOS is limited in what it can play. Plex has to transcode, and chooses x264 because that is IOS’s preferred profile for videos.
Reference iPhone-Compatible Video Formats - dummies

Video formats supported: H.264 video up to 1080p, 60 frames per second, High Profile level 4.2 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats; MPEG-4 video up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps per channel, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats; Motion JPEG (M-JPEG) up to 35 Mbps, 1280 by 720 pixels, 30 frames per second, audio in ulaw, PCM stereo audio in .avi file format.

Plex’s first purpose in life is to transcode so clients don’t have to.

And yes, in terms of raw power, your CPU is low in terms of PMS requirements.
Clock speed doesn’t relate to power any longer. The Arm7 architecture isn’t even 64 bit.
Reference Plex CPU recommendations, ARM processors are listed in the “no transcoding” area.
https://forums.plex.tv/discussion/314715/plexpass-and-transcoding-performance#latest

I understand you are disappointed, but you need a compatible system for transcoding. Your chosen system is not it.
Feel free to continue expressing your disappointment, but your ideas do not mesh with Plex idealogy.

I believe I’ve answered all your questions.

7

Hi,

There is simply no need to express my disappointment) I accept things as they are:

  • Plex team will not bother implementing proper hardware support for the processors they declare “not transcoding” even if these processors include modern DSP exactly for live transcoding )

  • Plex team does not want my money for Plex Pass as well as they do not want money of those many other users of the mainstream popular WD models on ARM7 and higher architectures with GPU and DSPs

  • iOS can playback MP4, although it prefers h264 for bandwidth considerations, but Plex decision engines ignore the fact that not optimizing a huge library is a better choice than wasting some (excessively available) bandwidth and translate the MP4 directly to clients rather than trying to transcode it live without proper hardware implementation for this. So fact #3, PLEX does not bother about problems the user may face.

Summary: PLEX team exists in idealistic parallel Universe and in this Universe people work for pure enjoyment and not for money (if they exist there at all).

Well, lesson learned. All the “Reviews” about magical new WD device with capability to translate up to 8 simultaneous streams each up to 8 Mbps )) is no more than a prepaid ADs.

The next time I will be smarter and buy a small tablet with good Intel Processor and install PLEX on in.

With this said, I must say I love PLEX design, web interface, their tedious thinking into details when it comes to end-user enjoyment ))

Maybe they just need to hire a couple of students from Software & Design dept. of any University in the vicinity?

8

@“malusik05@icloud.com” said:

  • iOS can playback MP4, although it prefers h264 for bandwidth considerations, but Plex decision engines ignore the fact that not optimizing a huge library is a better choice than wasting some (excessively available) bandwidth and translate the MP4 directly to clients rather than trying to transcode it live without proper hardware implementation for this. So fact #3, PLEX does not bother about problems the user may face.

I don’t think you fully understand video streams.
MP4 is a container type, not a codec.
h264 is a data (specifically, video) stream type, that goes in a container.
MP4 can hold several stream types, including h264 video.

Most Apple devices prefer MP4 container, with h264 video within them.

Manufacturers who use ARM processors do not include a standard graphic/dsp chip.
For every ARM Cortex-7 processor device you find, most have a different combination of DSP.

There is no easy way to develop for every ARM based system out there, as so many different NAS models exist that use different chips.

The fact they mention and allow transcoding for free on 3 WD NAS systems might be du to the fact those 3 use specific, easily accessed and program for, GPUs.

9

Bit late reply… but recently my server has begun lacking power… transcoder is maxed in speed (low quality setting)…
Got media on storage drive: a RAID 10 disk setup with 4 7800 rpm disks i guess,
Got a dedicated cache for the media storage drive through Romex which is 2 SSD in a stripe raid for performance…
Got transcoder libary on my OS drive for speed: a RAID 10 disk setup with 4 SSDs
Got 32 gb ram in it cant rememeber clock speed, but server type, high temperature…
CPU is 2 x Intel xeon E5345 at 2.33 Ghz,
Windows 10 64 bit os…
When i play something on my tv the transcoder service maxes out the cpu and the video starts buffering…
Tryed alot of tweaks and tingering but im beginning to think there something wrong with the process…
Any advices ??
Sorry for my bad english…
Morten S A