Rasplex performance help?

[vulcanjedi]

I have a 512mb rasplex.  This work pretty good.

My 256mb rasplex seemed unusuable but locally I dont seem to encounter any issues. I have a shared library and just enumerating whats not a large library seems to take a long time, even when I have hit that view before and I would imagine its already cached the thumbnails?

 

Anyways, I currently have the following:

Local - Direct play

Remote - Direct Play

Online - ask first

 

These are the default quality settings.

I've tired to change them all and have a very fast dl connection.

But cant seem to stream very large high res files w/o tons of buffering making it unwatchable?

 

Is this a limitation of the RaspPi?

 

[dlanor]

I have a 512mb rasplex.  This work pretty good.

My 256mb rasplex seemed unusuable but locally I dont seem to encounter any issues. I have a shared library and just enumerating whats not a large library seems to take a long time, even when I have hit that view before and I would imagine its already cached the thumbnails?

Anyways, I currently have the following:

Local - Direct play

Remote - Direct Play

Online - ask first

These are the default quality settings.

I've tired to change them all and have a very fast dl connection.

But cant seem to stream very large high res files w/o tons of buffering making it unwatchable?

Is this a limitation of the RaspPi?

The file size as such has absolutely no influence on playback ability, but the amount of data per time unit does. This bitrate is an absolutely limiting factor for all media players, and will limit the ability of such players to handle any media with a bitrate exceeding their capacity. And of course this capacity is lower for any unit having relatively cheap CPU and GPU chips, as compared to a full-scale computer with the latest graphics board.

My RPi has the capability to play media files with a bitrate of appx 20 Mbps without stutters. If I try at a higher rate like 23 Mbps the playback can start normally but shortly begins to stutter and pause to buffer, which then repeats in an endless cycle. So the limit of my RPi is somewhere slightly above 20 Mbps. But that RPi is running RasPlex from a USB3 stick and with some overclocking, both of which raise the capability compared to running RasPlex from an SDcard without overclocking.

Most of the time I leave my RasPlex quality settings at "Direct Play", except when I need to play some video known to have higher bitrate than 20Mbps, or one with incompatible CODECs. Then I switch the quality setting to 20 Mbps which activates transcoding to deal both with the bitrate limiting and with any CODEC problems.

A standard RPi setup using SDcard only and no overclocking will have a lower limit for the max bitrate of media to play without stutters.

I'm not sure exactly how much lower it will be though.
 

Best regards: dlanor

[T_ChaY]

But that RPi is running RasPlex from a USB3 stick and with some overclocking, both of which raise the capability compared to running RasPlex from an SDcard without overclocking.

I'm curious to know your overclocking settings. I'm running RasPlex with usb 3.0 stick too and my overclocking settings are
 

arm_freq=930

core_freq=450

sdram_freq=450

over_voltage=1

hdmi_force_hotplug=1a

hdmi_drive=2

gpu_mem_256=128

gpu_mem_512=200

hdmi_force_edid_audio=1

initial_turbo=30

Most of the time I leave my RasPlex quality settings at "Direct Play", except when I need to play some video known to have higher bitrate than 20Mbps, or one with incompatible CODECs.

It would be nice to choose  the quality settings when the movie is playing, this option should be in the menu bar. Return in Preference in order to change quality setting just for one media is annoying especially if you have to bring back the quality to direct play after watching your movie... 

[dlanor]

I'm curious to know your overclocking settings. I'm running RasPlex with usb 3.0 stick too and my overclocking settings are
 
arm_freq=930
core_freq=450
sdram_freq=450
over_voltage=1

Those four settings are the main ones affecting clock speeds and functionality (higher speed requires higher voltage).
My own values for those settings are:

arm_freq=950
core_freq=450
sdram_freq=450
over_voltage=4

When I use as low over_voltage level as you have my RPi becomes unstable, but this may be individual per unit too.
Even though we're used to thinking of all electronics as digital nowdays, their basic nature is always analog.
 

hdmi_force_hotplug=1a

Do you really use "1a" ?
Hopefully that is accepted the same as "1", but "1a" is not really a defined value AFAIK.
 

hdmi_drive=2
gpu_mem_256=128
gpu_mem_512=200
hdmi_force_edid_audio=1

Those settings are just for HDMI behaviour and the GPU/CPU memory split.
The split does have a strong influence on program efficiency, but I always go with the default defined for current RasPlex version.
(They've varied that setting in the released "config.txt" for recent RasPlex releases.)
 

initial_turbo=30

This setting only forces turbo mode for the first 30 seconds after boot start.
I don't use this, partly because i seldom need to boot, and I don't consider the slight speed difference of forcing turbo mode to be worth the possible risks. Normal ondemand overclocking is sufficient for me.
 

It would be nice to choose  the quality settings when the movie is playing, this option should be in the menu bar. Return in Preference in order to change quality setting just for one media is annoying especially if you have to bring back the quality to direct play after watching your movie...

Having those controls during playback would simplify such cases, but it's not the kind of change that it would be appropriate to implement specifically for RasPlex. That would give us a GUI incompatible with the mainstream PHT releases. So this is something to suggest for implementation by the Plex team.

On the other hand, when the transcoding decision methods have been improved sufficiently, according to current plans, we should no longer have to switch settings this way, as the program should recognize the cases for which transcoding is needed even when the setting is "Direct Play". (That applies both to CODEC incompatibilities and to bitrates exceeding 20 Mbps). This is partially implemented in the current release candidate, though I think it still needs some 'tweaking'.

Best regards: dlanor

[T_ChaY]

Thank you Dlanor for all this usefull information ! :)

So, for you, i don't have to use those settings below : 
 

hdmi_force_hotplug=1a

hdmi_drive=2

gpu_mem_256=128

gpu_mem_512=200

hdmi_force_edid_audio=1

initial_turbo=30

I found it in an old topic in this forum...

[dlanor]

Thank you Dlanor for all this usefull information ! :)

So, for you, i don't have to use those settings below : 
 
hdmi_force_hotplug=1a
hdmi_drive=2
gpu_mem_256=128
gpu_mem_512=200
hdmi_force_edid_audio=1
initial_turbo=30

Those settings will not affect RasPlex speed after completed boot, but they do have other purposes.

However, the important ones are already present in the "config.txt" supplied in the RasPlex firmware image,
and modifying the gpu_mem setting can have negative effects on the functionality,
as RasPlex may run out of memory for some operations (either for CPU or GPU).
So it's best to leave most things unchanged unless you have some specific purpose needing them changed.

For example, some time back my brother needed to use RasPlex with an old 4:3 CRT TV connected by SCART, and using the composite video output of the RPi. So for that usage I had to remove the "hdmi_force_hotplug" setting and set "sdtv_mode=2" and "sdtv_aspect=1".
But for a normal modern TV set I would skip changing that stuff, and leave any original entries for them in "config.txt" unchanged.

Best regards: dlanor

[gtjack9]

Does anyone know if the raspberry pi 2 b+ (I think that’s the one) can handle higher bitrate video processing as the raspberry pi b+ I’m using currently works surprisingly well and I think that my main restriction is actually my home network speed (Ethernet wall adaptors) which runs at 200 Mbits or 25 MBps which may be lower than my data stream. So either the pi is the bottle neck or the network is but I can’t seem to find a live bitrate overlay while playing content which would help a lot. Any help appreciated.

[ac4lt]

We’ve played blu-ray rips on a pi2 using rasplex with average bitrates of 30Mbps without issue (it’s a Pi2 on ethernet).

There’s a site, http://jell.yfish.us/, that has the same clip encoded in AVC and HEVC at 1080p and 2160p resolutions at various bitrates. You can make a “home movies” library with those clips and it becomes a great way to evaluate how well your client can direct play. I recall doing the test on the Pi2 but don’t remember whether it was Rasplex or PMP but I can try to run it again and let you know what the top reliable bitrate was for my system.

[dlanor]

@gtjack9 said:
Does anyone know if the raspberry pi 2 b+ (I think that’s the one) can handle higher bitrate video processing as the raspberry pi b+ I’m using currently works surprisingly well and I think that my main restriction is actually my home network speed (Ethernet wall adaptors) which runs at 200 Mbits or 25 MBps which may be lower than my data stream. So either the pi is the bottle neck or the network is but I can’t seem to find a live bitrate overlay while playing content which would help a lot. Any help appreciated.

I’m 99% sure that your problem is due to the powerline adaptors.

I’m not sure how the electric wiring of your house is implemented but it’s very common to separate the wiring of different rooms (or groups of rooms), connecting them to different fuse boxes and different power meter windings, which means that there will be significant inductance blocking high frequency transfers between the different wire networks of those rooms (or groups). And of course all signals passing through powerlines are also subject to power spike interference from normal electrical equipment (stoves, washing machines, and what have you), as well as various high-frequency interference sources (microwave ovens etc), since the signal fed to the powerline is a modulated RF frequency similar to WiFi signals except for being transmitted in wires.

Powerline adaptors work best only when the power wiring is simple, using a single shared fuse for all outlets which are thus also fed through a single power meter winding.

Even the old RPi1b model is capable of video playback at bitrates like 20 Mbps, but that’s not going to work on a network where the physical limit is so close as 25 Mbps, as you need some transfer rate margin to cope with occasional retransmission needs for missed packets. And when you add in the problems specific to powerline adaptors, those will in many cases ruin playback results even for much lower bitrates.

Another factor to consider is whether or not you use the “Secure connections” option of the PMS server.

Many people don’t realize that enabling this option causes all traffic both to and from each client to be encrypted, which means that a client must decrypt every single byte of the playback streams for both audio and video. That’s a significant load for so simple a computer as the RPi1, so this will significantly lower the maximum bitrate it can play without stutters. The RPi2 can handle this much better though the same principle still applies. The top bitrate limit is still lowered from what it would be without encryption, but the RPi2 is fast enough for that not to matter.

Btw: I have disabled “Secure connections” for my own PMS server, as some of my extended family use RPi1 clients to access my Plex library.

Best regards: dlanor

[system]

@gtjack9 said:
Does anyone know if the raspberry pi 2 b+ (I think that’s the one) can handle higher bitrate video processing as the raspberry pi b+ I’m using currently works surprisingly well and I think that my main restriction is actually my home network speed (Ethernet wall adaptors) which runs at 200 Mbits or 25 MBps which may be lower than my data stream. So either the pi is the bottle neck or the network is but I can’t seem to find a live bitrate overlay while playing content which would help a lot. Any help appreciated.

Upgrade your powerline adapters, I upgraded all of mine recently (in areas where I have no Ethernet) and there’s plenty of bandwidth. Have a look at the TP-LINK TL-PA8010PKIT AV1200

Regards

[KodeStar]

Would upgrading his powerline adapters make any difference? The RPi has a 100Mbps connection and his powerline adapters are 200Mbps

[Afullmark]

@KodeStar said:
Would upgrading his powerline adapters make any difference? The RPi has a 100Mbps connection and his powerline adapters are 200Mbps

But you won’t be getting that speed; it’s the theoretical speed, in ideal or perfect situations. Do a local speed test between the two power lines in question; perhaps plug in a laptop via ethernet to one power line and transfer and file to it from your main computer.

Someone here will know how to SSH into the pi and run a speed test direct, but i don’t.

[system]

@KodeStar @gtjack9

See this http://www.smallnetbuilder.com/tools/charts/powerline/view

Regards

[benjaminwolf]

@dlanor said:
Another factor to consider is whether or not you use the “Secure connections” option of the PMS server.

Many people don’t realize that enabling this option causes all traffic both to and from each client to be encrypted, which means that a client must decrypt every single byte of the playback streams for both audio and video. That’s a significant load for so simple a computer as the RPi1, so this will significantly lower the maximum bitrate it can play without stutters. The RPi2 can handle this much better though the same principle still applies. The top bitrate limit is still lowered from what it would be without encryption, but the RPi2 is fast enough for that not to matter.

Btw: I have disabled “Secure connections” for my own PMS server, as some of my extended family use RPi1 clients to access my Plex library.

Worth noting in addendum, using the PI2 with openVPN running 2048bit encryption works fine at bitrates over 20Mbps. However, running the Secure connections AND openVPN encryption, I sometimes encountered issues. It’s best to keep it to a single encryption method if possible using the PI2. And as you said, no encryption for PI1s.