[Merged] Power Saver feature

[Hex]

NOTE: As of 6th Aug there were some bugs that were noticed and are actively being removed. As of 10th Aug the bugs are squashed. Will be merged in a couple of days Merged as of v2.5.2

Hello guys, need your help in testing power saver functionality for ES. I shall also post compiled binaries later for all RPi s.

PR submitted : https://github.com/RetroPie/EmulationStation/pull/172
Repository : http://github.com/hex007/EmulationStation
branch : feature-powersaver
Latest Binary : https://retropie.org.uk/forum/topic/11304/testers-needed-power-saver-features-pr-172/153

• Enable the feature in: OtherSettings > Enable Power Savings Is Enabled by default now
• Dim and blank screensavers aren't triggered if PS enaled. All screensavers work nicely with PS
• PS is disabled if you have video screensaver enabled which works. PS works dynamically with VS giving you best power savings
• PS is disabled when you are on the gamelist which has videos.
• PS can be forced on such gamelist by changing views to "Detail" instead of "Video" or "Automatic"

You can use @meleu 's tool to compile if you cannot wait till I upload binaries. I shall also be accepting binaries from testers so if you were able to compile it then i can post it.

Raspberry pi 1/Zero/ZeroW : https://www.dropbox.com/s/o7v4ohrud8ugsyv/emulationstation_feature_powersaver?dl=0
Raspberry pi 2/3 : URL

[meleu]

@Hex Sorry, but I didn't get what's the purpose of that video... What are you trying to show?

[Hex]

The video is just to show that it works well with Video Previews. Status is shown at the bottom where ES version is shown. Hence the constant opening of Menu

[meleu]

@Hex What's that MUSIC PLAYER option in MAIN MENU? I don't see that in the official branch.

[Hex]

@meleu That is my implementation of an interface with an audio player for background music. Feel free to test that too. The python server backend is in audio-server folder of my master branch

[meleu]

@Hex Oh, I got it.

I just think that a video showing the exact version you're willing to see merged into the official branch should be a better illustration. :-)

By the way, what exactly the Power Saving feature do to save power?

[Hex]

@meleu In ES there is a loop that receives key presses/events. The most cpu intensive is a infinite while loop. I have modified it to wait for events rather than checking for event every cycle. It dynamically switches between polling and waiting for a great feature. The rest of the commit is just for wrapping and interfacing.

For the exact location of this feature : https://github.com/RetroPie/EmulationStation/pull/172/files#diff-0d7037121f70d0897714deabb3ea71e1R302

[meleu]

@Hex Looks like the most elegant approach than the infinite while loop. Is there any disadvantage in making PS enabled by default?

[Hex]

No there isnt and disadvantage but it is currently in testing so I have added a switch to enable and disable it. When it is ready after testing then I can enable it by default.

[meleu]

@Hex it somehow reminded me the Observer Pattern when I was studying Design Patterns back in 2009. :-)

[cyperghost]

@Hex I like your build very much.

In ES there is a loop that receives key presses/events.

I guessed that... I already told @pjft and you (??) in this thread. Why is there a loop wating for key events? Triggers to interrupts are a good way avoiding this. So you hunted that nasty workaround down :D

I have a "wish" to the Music Player.... Would it not be better to use mpg123 instead OMX Player? Just for background? The intention is following. OMXPlayer is already used for video playback and video preview. To have an independent process use an independent software just for background. MPG123 gots only 2% CPU usage. The control is just easy and you don't need a python backend.

STOP/PLAY ... even restart can be done by script (or if you develop ES in C++ there are much more options I guess)

Start/Stop Toogle, Start if mpg123 isn't started.sh

#!/bin/bash 
#Toggle MPG123 Music Player to mute/unmute condition
#Simple by checking running PID and sent -STOP or -CONT term
#Is no PID of MPG123 is available it will be launched
 
 
command="mpg123"
 
pids="$( pgrep "$command" )"
 
if [[ -z "$pids" ]]; then
    "$command" -Z /media/usb0/BGM/*.mp3 >/dev/null 2>&1 &
    exit 0
fi
 
for pid in $pids; do
    state="$( ps -ostate= -p "$pid" )"
 
    stopped=0
 
    case "$state" in
        *T*)    stopped=1 ;;
    esac
 
    if (( stopped )); then
        kill -s CONT "$pid" >/dev/null 2>&1
#        printf '"%s" (%d) has been unpaused\n' "$command" "$pid"
    else
        kill -s STOP "$pid" >/dev/null 2>&1
#        printf '"%s" (%d) has been paused\n' "$command" "$pid"
    fi
done

The Next Track command is simply
It kills mpg123 and restart it again in random mode ... so you randomly got BGM music. Hey... It's a decent ( @Hex - what the hell is your background song?) background music and not your sisters beloved POP album :D

#!/bin/bash
#This changes track by killing musicplayer
#and reloading it
 
pkill mpg123 >/dev/null 2>&1
sleep 1
mpg123 -Z /media/usb0/BGM/*.mp3 >/dev/null 2>&1 &

STOP

#!/bin/bash
#This STOPs musicplayer
 
pkill -STOP mpg123

CONTINUE

#!/bin/bash
#This STOPs musicplayer
 
pkill -CONT mpg123

Even we can using BGM in gameplay via User Menu

#!/bin/bash
#This STOPs musicplayer
 
pkill -CONT mpg123; exit 2

[Zigurana]

@Hex Hi, did you do any power consumption profiling with PS enabled/disabled?
I am wondering how much this actually saves in terms of power consumption.

I think one way to do it would be through one of those usb-power consumption doodaa's, but they might not be precise enough.
In any case, this is very relevant to my interests, with the RaspiBoy coming up soon!

[cyperghost]

@Zigurana May you test out please?

The CPU usages are triggered in this thread
https://retropie.org.uk/forum/topic/11178/emulationstation-cpu-usage

It's a the STANDARD ES for RetroPie 4.2
We ( @Sano and me) used top for CPU usage measurement

[Sano]

@cyperghost
I also used pidstat (part of sysstat package) that monitors the CPU usage of a single PID :)
@Zigurana
you may try powerstat or powertop

[Hex]

@cyperghost I wrote the server in 2012 when Raspberry pi 1 was released. I had the source code and it was well designed enough that it didnt take long for me to write an interface. The best feature is that all control requests silently fail if backend is not running. The Music player is very advanced with a websockets server support already coded into the backend thus if a day comes to incorporate a full fledged MusicPlayer it would be a breeze.

[Hex]

@Zigurana I dont have the USB doctor device so I cannot test it. Someone else can if they have one.

[cyperghost]

@Hex Sorry I missed your post!
Yes the phython backend works surely fine but it is a script that has to be configurated. That's my main misgiving or may I am wrong? I think easy access can be givento users by a standarized playlist location and in this playlist all songs from different locations can be stored...

Sorry for being inconvinient :)

About your PR... can you give us a compiles binary please?

[Hex]

@cyperghost I shall provide binaries for Pi 1/Zero only. Pi3 is fast enough to compile in 10 mins and I dont have an sdcard for it :(

There is no configuration needed. Plays audio from all files including videos downloaded from youtube. It can be controlled from android app too if needed (needs extended version).
On the backend it uses Aplay and avconv which are both available on the raspbian/retropie

[Hex]

Pi zero/1 binary is now available. It has two modifications done to the main branch.

• Power saver mod
• Wide menu mod (for my 3.5inch display)

The wide menu mod should not interfere with any other functionality.

[cyperghost]

That was quick my results are following.
0. I used top

1. The mod seems to work
2. I tested on a fresh 4.2 RPi0/1 image
3. Non overclocked RPi0 attached with 1 WLAN Stick LogiLink, 1 Controller
4. HDMI output

My outfindings:

Action                  ES branch       CPU usage
--------------------------------------------------
Reboot                  2.1.5RP         30-35%
Select NES 12 Roms      2.1.5RP         65%
Start Rom, back to ES   2.1.5RP         65%
Screensaver DIM 1min    2.1.5RP         10-15%

Reboot                  2.3.2RP PS off  40%
Select NES 12 Roms      2.3.2RP PS off  67%

Reboot                  2.3.2RP PS on   5-10%
Select NES 12 Roms      2.3.2RP PS on   45%
Select NES 12 Roms 5sec 2.3.2RP PS on   5-10%
Start Rom, back to ES   2.3.2RP PS on   65%
Start Rom, back ES 5sec 2.3.2RP PS on   5-10%

Bugs

Screensaver seem to be disabled in this mod ... but this is already told in "Info note"