Prevent Android “process is bad” error

Question

The process is bad error does not seem to be very well documented, and I have only been able to find workarounds. I am instead interested in the cause of this error and how to prevent it from happening, and not how to manually handle it through rebooting, relaunching app, etc.

My particular application uses an AlarmManager to launch an IntentService which runs for ~10s every ~30s. This is called on creation of the application:

Intent serviceIntent = new Intent(appContext, MyService.class);
    serviceIntent.putExtra("service_extra", extra);
    launchService = PendingIntent.getService(
            appContext,
            LAUNCH_SERVICE_REQUEST_CODE,
            scanIntent,
            PendingIntent.FLAG_UPDATE_CURRENT
    );
    alarmManager.setInexactRepeating(
            AlarmManager.RTC,
            System.currentTimeMillis() + interval,
            interval,
            launchService
    );

This works as expected most of the time. However, very occasionally the service will fail to launch for an indefinite period, sometimes hours at a time. The following error is seen every ~30s, so I know my alarms are attempting to launch the IntentService as scheduled, but the attempt fails with a process is bad error.

Unable to launch app com.example.android/10024 for service Intent { cmp=com.example.android/.MyService (has extras) }: process is bad

This is fixed by simply reopening the app. But I need to know how to prevent it! The purpose of this service is to run in the background while activities are stopped or destroyed, so it must prevent this error without any user interaction or workaround.

Answer 1

Good Chance is that it has to do with the handling of the activity's lifecycle.

It reminds me of a case I recently solved without fully understanding it because the documentation is not very specific on what you can rely on after onStop() is called on your Activity. And what exactly you shouldn't do...

So I can only give you some hints:

If my guess is right, you have problem with not being properly restored, when your App is (partially) removed from memory. Try setting the limit for background-Apps in the developer-settings to "none". I suspect that with this setting your problem will be completly reproducable when puting it to background. Otherwise you probably can stop reading here.

I had a thread that kept on running after onStop() that also kept some references. Stopping the thread in onPause() and also waiting for it to finsh solved my problem. I also needed to sync my onStop() because blocking onPause() resulted in onStop() coming in paralell. I also needed to move some of my initilization from onCreate() to onResume(). But that was quite obvious once I figured out at what to tear down in onResume() and onStop().

Probably the tipp with the static goes in the same direction.

Answer 2

The "process is bad" error happens after your service crashes a couple times. The system prevents it from coming back up and instead prints that message. You can clear the crash count by rebooting or more quickly by killing the system server:

adb shell killall system_server

This is effectively a "soft reboot" and will kill/restart any processes you've got going.