Periodic Job not running consistently when using Evernote Android-Job library

I am trying to schedule a periodic job to run every 15 mins by using evernote's android-job. The problem is job runs 2-3 times and then it doesn't run every 15 mins. Basically in span of 8 hours it ran almost 10-11 times when the device was sitting idle. Is there something I am doing wrong. The only requirement my job has is Network should be connected which was connected.

Does android-job library somewhat gurantees that job will run? This is my code for the job

   public class TestNetworkJob extends Job {

    public static final String TAG = "TestNetworkJob";

    @NonNull
    @Override
    protected Result onRunJob(Params params) {
        Timber.i("onRunJob");

        RetrofitUtils.getInstance().postSlack("TestCall: " + DateTimeUtils.getLocalizedDateTimeString(System
                .currentTimeMillis()));
        return Result.SUCCESS;

    }

    public static JobRequest buildJobRequest() {
        return new JobRequest.Builder(TAG)
                .setUpdateCurrent(true)
                .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
                .setPeriodic(TimeUnit.MINUTES.toMillis(15))
                .build();
    }
}

Basically in span of 8 hours it ran almost 10-11 times when the device was sitting idle

That sounds like standard Doze mode behavior, which you will encounter on Android 6.0+ devices.

I thought that was the whole point of using job-scheduler APIs

Oh, $DEITY, no. The point behind using JobScheduler (or wrappers around it) is to be friendly to the battery.

So how can we make sure a job is run every 15 mins?

In general, you don't.

Google would like you to stop polling and switch to Firebase Cloud Messaging, for server-side push messages. You're welcome to experiment with setAndAllowWhileIdle()/setExactAndAllowWhileIdle() on AlarmManager. But, on the whole, the War on Background Processing means that doing periodic background work is difficult at best.