Raspberry Pi 5 Suspend/PowerOff, WakeOnLan, "WakeByBuiltinRTC"

Dridil

I am on a project to setup an standalone server with an RaspberryPi 5, PCIe DVB-C dual tuner card and tvheadend. Recorded files are stored on the Pi. Since energy prices go up and up caused by 2 special guy's I want to delete my old HTPC and switch to a RaspberryPi.

I have this Pi5 reserved for another project for later but I am courius to test this out now. If it is a seccess I will buy an other Pi5 with less RAM.

My goal:

Only power up the Pi when a recording is running or a client(AndroidTV Box with Kodi) is connected(Watching or setup a recording) to the Pi.
Wake the Pi with its built in RTC for a recording
Wake the Pi with WakeOnLAN by AndroidTV Box(Kodi)

As an info:

Expected runtimes for recording or watching is 10h per week.
Expected power(With installed Card) on Suspend/PowerOff 0.024W (POWER_OFF_ON_HALT=1 in config.txt)

My current running setup:

RaspberryPi 5 8Gb RAM
Geekworm X1010 PCIe Expansion Board
Digital Devices PCIe Cine C/C2/T/T2 (V7) with installed drivers
Installed Tvheadend(Running as service) all fully setup ready for recordings

I have found some scripts for regular PC but they are a bit old and made for x86/x64.

Where i need you guys for help:

Requirements for Suspend/PowerOff, WakeOnLan, "WakeByBuiltinRTC"
Setup a script made for the Pi5 for Suspend/PowerOff, WakeOnLan, "WakeByBuiltinRTC"

I am switching from DVBViewer to Tvheadend and I am new on Pi5(But not Pi3, Pi4)

I am curious for your Input and looking forward to a success!

DeltaMikeCharlie

From a TVH perspective, this may help to determine when the Pi can sleep and when the Pi should wake:

https://docs.tvheadend.org/documentation/development/json-api/api-description/status#status-activity

Dridil

As a startingpoint for the Pi5:
According to this, this will wakeup the Pi after 10 min:
echo +600 | sudo tee /sys/class/rtc/rtc0/wakealarm sudo halt
Works pretty well as a test!

From a TVH perspective, this may help to determine when the Pi can sleep and when the Pi should wake:
https://docs.tvheadend.org/documentation/development/json-api/api-description/status#status-activity

DeltaMikeCharlie ~~Is this a Jsonobject getting from the API?~~ It is 🙂. I guess getting it with a curl?

One important question comes in mind, well actually two:

Which script language should I use? Plain shell?
Running as service or cronjob?

DeltaMikeCharlie

Dridil I guess getting it with a curl?

This depends on the answer to Q1. If you use Python, for example, the language has its own HTTP and JSON parser modules. If you decide on a shell script, either curl or wget should work well.

Dridil Running as service or cronjob?

Unless you really want to write your own service, cron already comes free with your operating system.

The API call answers the questions, "Is it safe to sleep now?" (connections & subscriptions) and "When should the system wake?" (activities). It does not answer "When will it be safe to sleep?" To answer that, you would need to test for active recordings dvr/entry/grid_upcoming with a filter on status and then inspect the stop time. If there are none, someone is probably watching live TV.

Good luck.

Also: Please consider sharing your solution on the forum when it's complete. Other users may find it useful.

Dridil

DeltaMikeCharlie This depends on the answer to Q1. If you use Python, for example, the language has its own HTTP and JSON parser modules. If you decide on a shell script, either curl or wget should work well.

I assume you would prefer Python for that?

DeltaMikeCharlie Unless you really want to write your own service, cron already comes free with your operating system.

Would cron be better suited to running a Python script every minute?

DeltaMikeCharlie Also: Please consider sharing your solution on the forum when it's complete. Other users may find it useful.

I will definitely do that, but it will take some time and testing.

DeltaMikeCharlie

Dridil I assume you would prefer Python for that?

No, not really. I've done a bit of work with Python recently, so it is freshest in my mind. However, I have been using shell scripts since the 1980s and a shell script with curl should also work just fine. In both, you would have to check for error codes to see if TVH was actually running, etc. Same principle, different syntax.

Dridil Would cron be better suited to running a Python script every minute?

I don't know. You would have to try. With a polling interval of 1 minute, given that the API load on TVH would be the same, then system load/performance would depend on how comparatively resource heavy bash+curl (or whatever) and Python are. My guess is that the difference would be negligible with bash+curl having a slight advantage.

bash should come standard on most systems, where as curl and Python may have to be installed.

DaveH

DeltaMikeCharlie With a polling interval of 1 minute, given that the API load on TVH would be the same, then system load/performance would depend on how comparatively resource heavy bash+curl (or whatever) and Python are. My guess is that the difference would be negligible with bash+curl having a slight advantage.

If the same script/prog is supposed to be run every minute then I wouldn't use cron or anything else to schedule it. I would instead use an infinite loop structure for the script, with a sleep (or whatever the equivalent is) for a minute at the bottom of the loop. That would avoid the overhead of starting the program, and stopping it, every minute.