Flutter Android ANR reported in Google Play Console – main thread shows android.os.MessageQueue.nativePollOnce

[vijaymsc]

We are observing ANR reports in production for our Flutter Android application distributed via the Google Play Store.

The ANR stacktrace captured in Play Console shows the main thread waiting in:

   at android.os.MessageQueue.nativePollOnce(Native method)
   at android.os.MessageQueue.next(MessageQueue.java:339)
   at android.os.Looper.loopOnce(Looper.java:176)
   at android.os.Looper.loop(Looper.java:324)
   at android.app.ActivityThread.main(ActivityThread.java:8547)
   at java.lang.reflect.Method.invoke(Native method)
   at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:582)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1061)

The native portion includes:

Thread-3 (native):tid=12 systid=24801
#00 pc 0x4f85c libc.so (syscall + 28) (BuildId: 6df9129278d4aa93fd96a5fdd121f30b)
#1 pc 0x54430 libc.so (__futex_wait_ex + 144) (BuildId: 6df9129278d4aa93fd96a5fdd121f30b)
#2 pc 0xc0e08 libc.so (pthread_cond_wait + 72) (BuildId: 6df9129278d4aa93fd96a5fdd121f30b)
#3 pc 0x1bd28 split_config.arm64_v8a.apk + 80625664
#4 pc 0x52fcc split_config.arm64_v8a.apk + 80625664

This indicates that the main thread appears to be idle and waiting for messages.

However, the ANR is categorized as User-perceived ANR in Google Play Console.

Production Impact
From Play Console (last 7 days):
24,091 ANR events
12,816 affected users

[vijaymsc]

ANR-stacktrace.txt
refer the stacktrace from playconsole

[lehcar09]

Hi @vijaymsc, thank you for raising this issue. Can you share what Firebase products and SDK version are you using? And, by any chance were you able to reproduce the issue? If so, could you provide the steps you've taken when you encountered the issue? or does the issue occur on certain devices and/or android versions?

[google-oss-bot]

Hey @vijaymsc. We need more information to resolve this issue but there hasn't been an update in 5 weekdays. I'm marking the issue as stale and if there are no new updates in the next 5 days I will close it automatically.

If you have more information that will help us get to the bottom of this, just add a comment!

[vijaymsc]

@lehcar09

Build gradle
implementation 'com.google.firebase:firebase-messaging:25.0.1'
implementation 'com.google.firebase:firebase-crashlytics:20.0.3'
implementation 'com.google.firebase:firebase-analytics:23.0.0'
implementation 'com.google.firebase:firebase-bom:34.6.0'

flutter yaml
firebase_analytics: 12.0.2
firebase_core: 4.2.1
firebase_crashlytics: 5.0.2
firebase_messaging: 16.0.2
cloud_firestore: 6.1.0

We are using these Firebase products, and the issue is not reproducible locally. I will attach the details of the affected devices, including their state (background/foreground).
Previously, I shared the full stack trace from the Play Store—kindly refer to it for your reference.

[lehcar09]

Thank you for that information @vijaymsc. Usually it is very difficult to look at ANRs in isolation and figure out what's wrong. I did some digging, and based on Android documentation, stack trace that contains nativePollOnce are generally not actionable.

Note: Ignore input dispatch ANR clusters that say "nativePollOnce" or "main thread idle." These usually correspond to ANRs where the stack dump was taken too late. They're generally not actionable so can be ignored. In general, the actual ANR issues will be present in other clusters, so real issues are not being hidden. See nativePollOnce for more details.

Unfortunately, without constantly reproducing the issue, it would be difficult to investigate the issue. For now, I would suggest try updating to the latest Firebase SDK version and see if there's any improvement in occurences.

I'll keep this open for now. That said, if anyone can see any commonalities between these ANRs, or even better, code snippets or minimal reproducible examples, please share it with us. It'll really help us move this investigation forward. Thanks!