🧠 Investigating Nothing OS CPU Idle Behavior — Wake Locks & Background Services

JochieSantiago

Hey everyone,

I’ve been testing my Nothing Phone (Nothing OS 3.5) with ChatGPT (GPT-5) to understand why the CPU doesn’t seem to enter deep idle — even when the screen is off and nothing’s running in the foreground.

We went through a full diagnostic session using ADB to identify which services or apps might be holding wake locks or background jobs that keep the CPU partially active

⚙️ Background

The issue started with unusually high idle CPU usage (20–29%) and noticeable overnight battery drain (around 6–8%).

After checking dumpsys power, several partial wake locks were visible — mainly from Smart Center (com.nothing.smartcenter) and occasionally other apps using Firebase (like WhatsApp, Messaging, or TubeMate).

Smart Center’s BLE notification service in particular (NothingNotificationService) seems to stay active even when the phone should be sleeping.

🧩 Steps & Methods

1. Checking active listeners

adb shell settings get secure enabled_notification_listeners

Found Smart Center’s BLE notification listener constantly enabled.

2. Restricting background activity

We temporarily limited Smart Center’s permissions to see if it affects CPU sleep states:

adb shell am set-standby-bucket com.nothing.smartcenter restricted

adb shell cmd appops set com.nothing.smartcenter RUN_ANY_IN_BACKGROUND ignore

adb shell cmd appops set com.nothing.smartcenter WAKE_LOCK ignore

adb shell cmd appops set com.nothing.smartcenter POST_NOTIFICATION ignore

adb shell cmd jobscheduler cancel com.nothing.smartcenter

3. Forcing deep idle manually

adb shell cmd deviceidle force-idle

adb shell cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

CPU frequency started dropping from ~1.9GHz down to ~441MHz, showing that deep idle can be reached manually.

4. Testing third-party apps

Some third-party apps (like TubeMate) were also seen holding KeepAlive jobs:

adb shell cmd appops set devian.tubemate.v3 RUN_IN_BACKGROUND ignore

adb shell cmd appops set devian.tubemate.v3 WAKE_LOCK ignore

adb shell am force-stop devian.tubemate.v3

📊 Current Observations

With restrictions in place, CPU frequency does fall lower during idle, sometimes reaching 441MHz.

dumpsys power shows significantly fewer active wake locks.

Still under testing to confirm long-term battery impact and if Nothing OS automatically re-enables those background services over time.

🔄 Reverting the Changes

To restore everything:

adb shell cmd appops set com.nothing.smartcenter RUN_ANY_IN_BACKGROUND allow

adb shell cmd appops set com.nothing.smartcenter WAKE_LOCK allow

adb shell am set-standby-bucket com.nothing.smartcenter active

There’s also a revert_all_changes.bat script prepared to reset all settings at once.

💬 Closing Notes

This doesn’t appear to be an app bug — it’s likely a system behavior tied to Nothing’s background daemons, Smart Center, and Firebase sync routines.

We’re still testing whether these restrictions improve idle drain over time.

Big thanks to ChatGPT (GPT-5) for helping me trace and document each step clearly.

Please, feel free to drop any suggestions or ideas.

Keep in mind that my device was not directly bought with Nothing, so it does not have warranty. At this point, I'm just trying different stuff out to see if anything helps with the battery life problems and the apparent causes of it. (At least for me)

Benestin Linson

JochieSantiago

✅ My Experience on CMF Phone 2 Pro (Nothing OS 3.2 – Latest Software Version)

Hey! Thanks for sharing all the details — this is actually super helpful.

I’m using a CMF Phone 2 Pro (Nothing OS 3.2 based) on the latest software version, and I’m also facing similar idle battery drain issues. I’ve been using this device for about 5 months, and during the first 1–2 months the idle drain at night was almost perfect — usually just 1% overnight and the overall battery usage looked really optimized.

However, after updating to the recent software builds, I’ve noticed the overnight idle drain jumping to around 5–6%, sometimes even more. This happens even when the phone is literally doing nothing.

To rule out app-level problems, I’ve already:

Turned off background battery usage for Instagram, Google, Chrome, WhatsApp, Telegram, games, etc.

Restricted unnecessary background processes

Disabled auto-sync on a few apps

Checked app battery consumption history

Even after doing this, the overnight drain still remains the same — so I’m starting to think this is more of a Nothing OS/system background process issue, not individual apps.

Right now, the only workaround that fully stops the drain for me is switching off the device while sleeping, which obviously isn’t ideal.

Would be great if the dev team could take a look at this. The behavior definitely changed after recent updates, so maybe something (Smart Services, background daemons, or sync services) is staying active when it shouldn’t.

Looking forward to

any fixes or insights 🙌

@Rob ⚡️ @Carl

itsmeralph09

Mine's got only 1% - 2% battery drain in overnight idle. I just switched off some useless google bs like "nearby device scanning" and "unknown trackers scanning"

JochieSantiago

itsmeralph09 I already did all that. Still it has those Daemons that won't allow the SoC to go below 20% on idle

itsmeralph09

JochieSantiago

From 12am to 2am

From 2am to 4am (a noticeable drain of 1 to 2%, probably because my mobile data is turned on overnight since I'm waiting for my fiance's rcs messages, she's working night shift)

From 4am to 6am

JochieSantiago

itsmeralph09 from today

Anonymous993

Thanks OP - I really appreciate this level of technical analysis as a lot of these underlying system processes don't really reveal themselves on the stock Battery stats screen for anybody to ever notice or realise they are problematic, but can cause a lot of battery drain…

I noticed Nothing X/Smart Center (which triggers Companion Device Manager very frequently/every unlock) is very excessive in it's Bluetooth usage. My 3a does enter deep sleep though just by restricting Nothing X background usage (I've also done a lot of other disabling of unnecessary Settings like Unknown Tracker Alerts, Location Wifi/Bluetooth scanning, "Smart" Wifi features, Android System Intelligence, etc…

CMF1_hacker

Hi and excellent technical thread.

I have a NP3 running NOS 4.0b ATM and can do whatever parallel analysis you'd like.

You're seeing massive WA-based battery draining. I never saw above 10%/hour video call usage.

I speculate that this is due to the developer settings that you change but I could be wrong.

Anyways, I usage chatGPT5plus daily and can help with any comparison control you'd like.

JochieSantiago

Any help is welcomed. And yes, there are some daemons and UI elements that act as a wakelock in the system, thus making some cores of the CPU to stay above 25%.

Also, WhatsApp has been contributing to the battery drainage, and I've tried everything there is and still no change. @CMF1_hacker in the 3.5 version, WhatsApp does not revert developer settings when it comes to motion and animation. So it must be a bug with the beta. At least on my end.

Now I've been running on 4G setting to see if that also contributes to battery life. I'm going to continue doing some more tests this week as I'm getting my Xiaomi 15T pro tomorrow so I'll use that as my daily and compare both the Nothing and the Tecno Pova (which both have also similar batteries, but one is SnapDragon and the other is a Mediatek).

I don't know if there's a member off the development team or software engineer in this community who can provide more info or insight on this matter.

CMF1_hacker

JochieSantiago yeah. I still get 10+h SoT on NOS 3.5/4.0beta and have no idle drain overnight really (maybe like 1%/h.)

This will work out to around 9h SoT from 25% over nearly 24h.

If you want me to check any settings with ADB just let me know below and I'll check them after I get the kids to sleep.

Also, this is with BT on the entire time as the CMFW3P demands that compared to my Garmin, which doesn't.

JochieSantiago

CMF1_hacker try to see if there are any kernels that keep your CPU from going below 15%

CMF1_hacker

JochieSantiago not really, I will try to attach 2 min of screen recording.

https://cdn.nothing.community/2025-11-04/1762280421-846068-screen-20251104-181932.mp4

I opened the CPU monitor, closed the apps by swiping up and then started the recorder (which are the spikes in the beginning).

Also, I find your overnight usage normal for me. I have 5g and WiFi on. I do use the nighttime mode (grey scale and notifications paused).

I really find the WA drain really high for you. Also, I think some of those social media apps are hogs (FB, IG, SC, etc…) so I don't install them and access them through browser.

I just did a WA video call and I think it was about 7 minutes and it used about 60+% of what I estimate to be 10%, so about 1% battery per minute, which looks consistent with your findings.

I find that the video-based apps like Camera run the SoC quite high, so that's not unexpected.

I also find 8-10% overnight (1%/hr) acceptable.

Anonymous978

CMF1_hacker I also find 8-10% overnight (1%/hr) acceptable

I get 8% battery loss overnight if I leave wifi data etc. turned on

But yesterday I overcharged to 100 (to calibrate accubattery) with nothing turned on, and six hours later it's 94%

What's going on with NOS that in idle its still taking 3/4th the loss of turning everything on?

My background apps are mainly wallpaper engine, whatsapp, accubattery

Anonymous978

@JochieSantiago Can you test for issues with battery calibration? When my 3A started giving battery issues, I let it die to 0 then overcharged it at 100, and it magically fixed itself, in fact giving even better battery life than what it gave out of the box. Same with my CMF Buds 2a.

JochieSantiago

I'm currently out looking for wedding rings 😅 but when I get back home I'll run the tests with the System Monitor app.

@Anonymous978 I have. Like twice. Still nothing. But that was in the beta. I have to do it again later today.

EDIT:

So here is a recording of the CPU. There are 4 cores that are always running steady, and overall processor does not go below 20%. If you skip to the end of the video, you can see I'm on OS version 3.5, and the kernel version the phones has.

https://cdn.nothing.community/2025-11-04/1762299938-33629-screen-20251104-192717.mp4

JochieSantiago

Anonymous978 currently testing that out using accubattery. Chat GPT recommends using adb to get what wakelocks are active (again), and suggesting to create a Macro Droid script to notify me each time the phone comes out of deep sleep.

JochieSantiago

Benestin Linson thanks for sharing. I'm currently working with chat GPT to make a Macro Droid script to detect and log any wakelocks that prevent the phone from deep sleeping

Benestin Linson

JochieSantiago

Sounds good! That script would be really helpful. If you get it working, please share it here — I’m also facing idle drain issues on Nothing OS 3.2 and would love to test it.

JochieSantiago

Benestin Linson of course!

Edit: so chatgpt can't create a Macro file that works with macrodroid. So that's dead.

CMF1_hacker

You know, I just had a really bad run with like 6h SoT but 48h runtime.

Also, my screen on time has dropped from 13.5h with NOS 3.5 to 12.5h with NOS 4.0beta to 10.5h recently.

Here's the data for the last 7 days or so

JochieSantiago

CMF1_hacker yours show that your device is able to enter deep sleep mode for a good period of time. Have you checked to see how soon it goes to deep sleep after the screen is off?