Help tracking down "System UI has stopped"

[ewill]

Here is the situation. I have just acquired a new device (Moto G6 Plus) running Pie. I am rooted. I have a large number of flows and everything was working perfectly on my old device (HTC 11+ running Oreo).

On my new device, very often a couple of minutes after restart, I get a "System UI has stopped" error - followed by errors in any application running in the foreground. I have discovered that if I disable all of my flows during startup, and activate them a few minutes afterwords I don't have this error.

I do have a number of "startup" flows, I have tried delaying them and having them execute in sequence - with a delay of 2 minutes after startup. My UI issues happen before any of my startup flows begin executing.

Occasionally, I will get the error when I have been running for a while, but that is far less frequent.

My question is - other than a prolonged trial and error process - is there any ideas for tracking this down? I am not on the EAP version. Does that EAP version have any Pie fixes - and should I try that?

Any other ideas?

Thanks in advance for your assistance.

[Desmanto]

This should be troubleshooted with the logcat. It seems to be the error from the OS itself. Automagic simply magnifiying the error. You can also use Automagic to run logcat after startup. Or you can logcat based on specific time using -t parameter.

[ewill]

Thanks for the suggestion.

I have tried to do a logcat (via adb) to catch what happens just before the freeze. It looks to me like Automagic has something to do with it, but I am not sure.

I have attached the last several hundred lines before the freeze - hopefully it is not too much to request that somebody take a look at it.

For the meantime, this is a workaround that I have discovered and it is working.

Just a matter of introduction:
- I have a convention for all flows that I want to be active. I name them starting with "a", (ie "aThis is a shortcut"). The main reason I do this is if all of my flows are turn off (ie I do a restore and automagic loads my flows and deactivates them), I have a quick way to activate the ones I want.
- I have a single flow that I use for all startup events. Any flows that I want to activate on startup, are called from that "startup" flow.

My workaround is to insert the following into my startup flow:
1 - turn off all flows named "a*"
2 - wait 2 mintues
3 - turn on all flows name "a*"
3 - do the rest of my startup activities.

Not ideal, but using this workaround my phone is perfectly stable.

Hopefully the logcat will help in troubleshooting, or figuring out the next step.

Thanks again.

[Desmanto]

So, you have tracked down that the error must be caused by one/several of the flows those are active. Based on the log, it seems to be something related to accessibility. This means flow with triggers UI Event and App Task Started/Ended. There can be some flow that have long loop or calculation and triggered during startup by some other non startup event. Example your startup have launched some UI with text "start" and you have flow with UI event and filtered for that keyword. Even thought UI event is not startup trigger, but it triggered based on the text "start" by other mean.

You maybe want to try to disable accessibility too, and check if the error persist.
The other way you can shrink down to the culprit is to let all the flow enabled. Wait until hang, then check at the statistic, find which flow has the longest duration or execution count. Those might be the culprits.

I have also a flowception which shows much more detailed statistic for my total flows. One of the function is to save all enabled flow into glovar. Next time I imported back the flow from reset, if the flow is not enabled automatically, I simply restore the saved flow state from the glovar.

[ewill]

Thank you very much for your guidance and suggestions! I was able to figure out the issue.

I have a flow that is triggered using the "Notification on Statusbar" either displayed or removed by any app. If I disable, or delay activating that flow by 2 minutes, all is fine. Through the statistics, I saw that this flow was called far more than anything else. Talk about bad design....

In the meantime, I have delayed the start, but I realize that I will have to rethink my approach.

Anyway, the purpose of the flow is to determine if I have an "important notification" and if so, display an LED notification. I used to have an app on the play store for that (there are several), but they don't work on my device. I also apply so logic to my definition of importance. For example, a missed call from somebody in my contact list is important. If the caller isn't on my contact list, it isn't important. The easy fix is to limit the apps that trigger the flow.

Anyway, thanks for the help!

[Desmanto]

During startup, several apps may create multiple notification. There can be also some leftover notification from previous boot. And yes, you have to limit the apps to make it more efficient.

[ewill]

I have redesigned my approach and limited the apps. Thank you for your guidance in helping me solve this!