Both my smartphones draining battery like crazy after last Merlin update.

[YoureAWizardMerlin]

Now before I start, let me just say that I am not directly blaming the update for my battery drain, it may just be a co-incidence.

I updated to 384.4_2 about a month ago, and ever since then I started getting incredibly bad battery drain when connected to my wifi network. I could tell it's when only on my wifi after using an app and seeing directly that as soon as my device is connected to my wifi, it starts recording incredibly high battery drain. The drain isn't showing up in Android battery settings and the wakelocks don't really look too high or out of place. At times I would get an 'unaccounted' reading in SystemPanel2 that would show more than 75% of my battery being drained for some unknown reason. Other times, this reading wouldn't show up but the battery would noticeably start draining faster than normal. Off wifi I can get about 1% of drain per hour. On wifi it's anywhere from as bad as 5% per hour all the way up to 11% per hour which makes being on wifi impossible.

I have now updated to 384.5 and I am still getting the issue. Both my devices are draining incredibly quickly on wifi. The battery drain starts at random intervals. Sometimes at 2:00am, sometimes at 4:00am. Sometimes at 00:00am (midnight) sometimes at 6:00pm, but generally on the hour. Disconnecting the device solves the problem.

I thought it could be an app that is just running at a scheduled time causing the drain. However I've wiped BOTH phones back to factory and just left them with zero apps (just stock) installed and still got the same drain. At this point I'm stumped. I would have considered a faulty device but both of them? At the same time?

Here are my settings on my RT-AC68U router. It's pretty old by now (if you want any more screenshots please ask):


Here's a few screenshots of the battery drain on my devices (Both Android 8, Sony XZP & HTC U11+):


I've been using Merlin for years and years with no problems at all and like I said I'm not blaming anyone for this problem except myself. I'd just like to know if there's any setting I should change or test I can make to try and narrow down the issue better. It may be just an issue on my phones but I really find that unlikely as this happened after a firmware update and it is affecting both my phones on 5Ghz.

Thanks

 

[AndreiV]

Well, we have no issue like that here.

I would "forget" the SSID's on your phones and reset the WiFi on them.

Then check all your apps for background activity. Many apps try to run in the background and updates can make changes to settings.

I kill at least a dozen apps on start up using Android Assistant, the difference in battery life is amazing.

 

[YoureAWizardMerlin]

Thank you very much for the reply. I've tried doing that, also tried setting up a static I.P. but neither resulted in any difference. The problem seems to persist also on the 2.4Ghz band but not quite as bad.

I'll try Android Assistant. I was already using Greenify, but the thing is, neither of my phones now have ANY other apps installed. Just the stock Android 8 with stock apps. Not rooted or anything. So it pretty much hast to be something with my RT-AC68U setup...

 

[martinr]

As an experiment, can you see what the drain is if you leave one of the phones next to the router (so the wifi signal is at its strongest)?

 

[Ronald Schwerer]

It could be app/OS updates being pushed in early morning hours. I have my Nexus 5 set to only update when charging and connected to wifi.

 

[YoureAWizardMerlin]

Hey guys I worked it out. It seems to be my PiHole. I don't know if the Merlin update has something to do with interfereing with it or not but as soon as I turned the PiHole off and just set the DNS back to auto through the router config panel the drain stopped immediately. Left it that way for about 5 days and it seems to have fixed the issue.

So now I need to find out why the PiHole is causing such significant drain. It never used to. I'm only running with the bare minimum blocklist too, only 125k domains blocked. I know some people who have over 2.5m and aren't having issues so I guess I need to find either the offending domain that is causing my phones to go haywire or what other part of the PiHole config is causing the drain issue.

 

[Twiglets]

You need to look at what Apps are running on your Phones and the IP Addresses they are accessing.
The only way for WiFi to cause this sort of drain is constant chatter to an IP Address that it can either NOT get to, does not return the data it is seeking or in some other way is seen as invalid including login/password data no longer working !!!
Can you identify something that does not work anymore when the Battery drain is happening.

The WiFi is not the fault BUT whatever is performing the constant chatter !!!

Is there some new app you have installed or new update to the version of Android ?
Is there some new 'block list' you have setup or added to Pihole. ?
Are you running any other 'Ad blocker' type Apps on the phones that may have updated ?

You may have to reboot the phones and go through the apps/processes that are automatically loaded 1 by 1, killing the process (stopping restart as well) and seeing if the chatter stops or drops in frequency.
The other option is reduce the blocklists to the minimum to allow the phones to function without the Battery Drain then add back the lists until you identify the list that causes the chatter again.

Finally, look at other changes that may have occured at the same time that Merlin was updated. These changes may be anywhere on your network that is impacting the ability of your phones to operate as they did. It could be coincidence that something else happened at the same time.

 

[YoureAWizardMerlin]

Hey mate. I've worked out that it really shouldn't be Merlin at all. The thing is, both the phones have been wiped back to stock so I have no other apps installed, and neither are rooted so I can't get access to low level debug results or anything else. All I can do is install an app that shows there's battery drain that stops when not connected to Wifi, and when connected to Wifi but with the PiHole not running. I thought it may be the Quad9 DNS I was using as the upstream DNS but I changed basically everything I could see in the settings, watched a bunch of YT videos and tried everything else I could.

I realise it's an issue with an app or service trying to "phone home" and when it doesn't work, it retries endlessly and causes drain. I just don't know what app or service it is because it isn't listed anywhere and logcat tells me nothing. At this point I either need to keep playing with the settings or just keep the PiHole disconnected entirely. It never used to happen so it may be some kind of issue with one of the other PiHole updates I made around the same time, but there's so many variables here that it's very hard for me to diagnose anything past "Well it has to be the PiHole because as soon as it's off, the drain stops". I just find it kind of weird that it never happened before even when I had like 1.8m domains in the blocklist and now I have the absolutely bare minimum default list that the install ships with and it's still causing the same issue. Tried also using a static IP on my devices but that didn't make any difference.

I mean at this point I'm using the bare minimum and still getting a lot of ads but battery drain at the same time. I'll keep testing and try to get to the root of the cause but I am not sure I'll get a definitive answer with how little info I have via the Android system panel.

 

[Twiglets]

Your last resort is to capture all the Wifi Traffic from one of the phones for 5-10 mins and go through the capture examining what is being called and what is failing/retrying etc.

Laborious but will find the culprit in the end !!!
I am sure you can get advice on how to do this efficiently from someone who knows on this forum (hint hint) but a quick google finds for Android:
https://www.computerworld.com/artic...monitor-wi-fi-traffic-on-android-devices.html

I would expect you can probably do this on the RaspberryPi with Wireshark setup appropriately, I don't have any experience of doing this so cannot help.

 

[DaveMishSr]

Now before I start, let me just say that I am not directly blaming the update for my battery drain, it may just be a co-incidence.

I updated to 384.4_2 about a month ago, and ever since then I started getting incredibly bad battery drain when connected to my wifi network. I could tell it's when only on my wifi after using an app and seeing directly that as soon as my device is connected to my wifi, it starts recording incredibly high battery drain. The drain isn't showing up in Android battery settings and the wakelocks don't really look too high or out of place. At times I would get an 'unaccounted' reading in SystemPanel2 that would show more than 75% of my battery being drained for some unknown reason. Other times, this reading wouldn't show up but the battery would noticeably start draining faster than normal. Off wifi I can get about 1% of drain per hour. On wifi it's anywhere from as bad as 5% per hour all the way up to 11% per hour which makes being on wifi impossible.

I have now updated to 384.5 and I am still getting the issue. Both my devices are draining incredibly quickly on wifi. The battery drain starts at random intervals. Sometimes at 2:00am, sometimes at 4:00am. Sometimes at 00:00am (midnight) sometimes at 6:00pm, but generally on the hour. Disconnecting the device solves the problem.

I thought it could be an app that is just running at a scheduled time causing the drain. However I've wiped BOTH phones back to factory and just left them with zero apps (just stock) installed and still got the same drain. At this point I'm stumped. I would have considered a faulty device but both of them? At the same time?

Here are my settings on my RT-AC68U router. It's pretty old by now (if you want any more screenshots please ask):
View attachment 13346 View attachment 13347

Here's a few screenshots of the battery drain on my devices (Both Android 8, Sony XZP & HTC U11+):
View attachment 13348 View attachment 13349 View attachment 13350

I've been using Merlin for years and years with no problems at all and like I said I'm not blaming anyone for this problem except myself. I'd just like to know if there's any setting I should change or test I can make to try and narrow down the issue better. It may be just an issue on my phones but I really find that unlikely as this happened after a firmware update and it is affecting both my phones on 5Ghz.

Thanks

Whenever an issue like this arises I always try flashing to OEM and back to Merlin. I realize that in your case it is a specific issue but sometimes it does seem to resolve issues.

 

[joegreat]

Now before I start, let me just say that I am not directly blaming the update for my battery drain, it may just be a co-incidence.

I realise it's an issue with an app or service trying to "phone home" and when it doesn't work, it retries endlessly and causes drain.

Maybe changing the Advanced options is an (intermediate) solution: Settings / Wi-Fi / Wi-Fi Preferences / Advanced options and the change "Keep Wi-Fi on during sleep" to "Only when plugged in" - the menu structure coild be named a bit different (dependent on the OS version) but at the end "Advanced options" is where you should go.

Of course a firmware update of the Smartphones (if provided by the vendor or Open Source version available) could also help to get rid of the issue.