Call for testing: background location updates

mardy · 20 May 2021, 19:05

Hi there!
I've been working on a few branches (you can find all the links here) to allow applications which are actively using the location service to continue running in the background, and therefore continue receiving location updates.

If you'd like to help testing this, please run

sudo ubports-qa install xenial_-_locationbg

on your phone, then reboot, and have fun

Please report any issues (including shortning battery life!) by adding a comment to this merge request.

Ciao,
Alberto

AppLee · 20 May 2021, 19:32

@mardy
:folded_hands: :folded_hands: :folded_hands: :folded_hands: :folded_hands:
Thanks a lot for your time. That's a really nice feature long awaited.

Can you tell us more about how to test and how it works ?
Simply because and app is using the location it won't go to sleep after timeout or shutting down the screen, is that it ?

cliffcoggin · 20 May 2021, 22:03

I too am interested in such an application. What advantage does it have over preventing suspension with UT Tweak Tool?

mardy · 21 May 2021, 10:55

@applee said in Call for testing: background location updates:

Can you tell us more about how to test and how it works ?
Simply because and app is using the location it won't go to sleep after timeout or shutting down the screen, is that it ?

Yes. Replying to both:

@cliffcoggin said in Call for testing: background location updates:

I too am interested in such an application. What advantage does it have over preventing suspension with UT Tweak Tool?

This is not an application, but a set of changes to the OS itself. It mainly consists of two parts:

The location service exposes a list of the application ID which are currently receiving location updates
Lomiri (new name for unity8) monitors that list, and sets the LifecycleExemption flag on those applications; the flag is removed when the application requests to stop receiving location updates.

So, it is similar to what the UT Tweak tool does, except that this is automatic, and lasts only for as long as the application is using the GPS.

This is just the first iteration: in the future, we would like to have it so that when an app requests access to the GPS, the user is given the choice between granting the permission to receive such updates in the background, or only when in the foreground.

cliffcoggin · 21 May 2021, 11:15

@mardy Thanks for the explanation, but it throws up other questions. Being a change to the OS:
[a] How will it be affected by OTA updates?
[b] How do I revert to normal OS if the change creates problems?
Pardon my caution, but I have little understanding of the matter or how to overcome problems.

AppLee · 21 May 2021, 17:13

Hi @cliffcoggin

I think I'm not mistaken if I say that the goal is to test it out for it to be integrated in the OS for the upcoming OTAs.

I see at least two easy ways to go back :

Switching channels
Using the UBports installer

AppLee · 21 May 2021, 17:16

@mardy
Thanks for your answer, I'll install it and will try to test it out, but I'm mostly at home for the moment so not many opportunities to test the GPS.

Thanks again for your work.

kugiigi · 21 May 2021, 17:30

I think one of the best app to test this is Activity Tracker. I won't be able to help with the test so I just suggested something

cliffcoggin · 21 May 2021, 22:44

@applee If switching channels is an easy way to restore a current OTA that is fine and I am happy to test this modification. Re-installation however is not an option for me as I have never been able to get the installer to work.

cliffcoggin · 22 May 2021, 14:29

I tested this today after a long struggle to copy the code from here to the terminal of my Nexus 5.

The test is in two parts using OSM Scout Server (with suspension enabled), Pure Maps, and Activity Tracker (with suspension enabled).

In the first part of the test I found that the lockscreen was prevented, consequently the display was continually on and the battery level dropped rapidly. That is something I would want to see fixed. Nevertheless the three applications mentioned all worked. I also tested that phone calls, text messages, and internet also worked. (I don't recall if the latter was using SIM or Wi-Fi.)

For the second part of the test I manually engaged the lockscreen with the power button. Every ten minutes I checked that the mapping continued to work, and battery levels were dropping at a more acceptable rate though I did not note any specific figures for power drop.

The one oddity was Activity Tracker which showed many data points while it was active, but when it was stopped and saved, only 4 data points were recorded instead of the expected 13. I don't know if that is an effect of the new software or something In Activity Tracker. It is not an application I use regularly.

Does this report help?

Cliff.

mardy · 22 May 2021, 20:06

Thanks @cliffcoggin ! I realized just now that not all the packages made it to the PPA: the lomiri changes are not there, and they are essential to get this functionality working fine. I'm still trying to understand what is the correct branch to use for lomiri, and then I'll rebuild the package. I'll keep you guys posted!

For the time being, better not use this PPA, as it's incomplete.

cliffcoggin · 22 May 2021, 23:55

@mardy OK. I will await developments.

To get back to stable channel I changed to RC which appeared to go well. I then tried changing back to stable channel, and it told me it was switching channels, but it remained on RC. Is that because RC is essentially the same as stable at the moment? Do I need to do anything more?

mardy · 23 May 2021, 05:09

OK, now the PPA seems ready

Please test it again, and sorry for the previous glitch!

cliffcoggin · 23 May 2021, 11:08

@mardy Initial indications are good. Lockscreen engages as normal, Sensor Status and Pure Maps show the correct location.

I'll perform a longer test next time I go out and let you know the outcome.

cliffcoggin · 23 May 2021, 13:53

@mardy Further information: the battery level dropped from 65% to 5% in less than three hours. (I don't know the precise time as the phone turned itself off while I was away from it.) That's probably similar to what it would have been before the modification.

kugiigi · 23 May 2021, 14:22

If i remember correctly, the main issue before is that location stops working when you lock the screen even if you disable suspension. I had to stop automatic locking whenever I use Activity tracker. I was lucky Bq E5's battertly is great so I was able to use it for many hours.

TotalRando · 30 Jun 2021, 22:19

Hey this just turned my GPS on! Thanks!

magdesign · 15 Aug 2021, 18:18

@mardy
Thanks!
After doing

sudo ubports-qa install xenial_-_locationbg

and rebooting my oneplus6 several times the GPS is finally working!

hsce1 · 30 Jan 2024, 16:41

Hey @mardy, do you know if your background location service implementation has survived the transfer to focal?

Edit: I guess I found the relevant MR: https://gitlab.com/ubports/development/core/lomiri/-/merge_requests/70

aimar · 1 Feb 2024, 20:52

Wow! How did I miss this feature? I have seen the last post and realize that it was available two years ago.
Well, BQ E4.5 OTA 25. I have just installed it, but I am not very confident it will work. I get some errors that make me suspect:

ubuntu-location-service-bin#####]
W: No sandbox user '_apt' on the system, can not drop privileges
E: Sub-process /usr/bin/dpkg returned an error code (1)
ERROR:ubports-qa:Failed to run 'apt full-upgrade'. See the output above for details.
mount: / is busy
WARNING:ubports-qa:Failed to remount root filesystem read-only.
WARNING:ubports-qa:Please consider rebooting your device.

I have rebooted the phone. This weelend I will test the background data adquisition.