How to start action at a fixed rate on Android?

Question

I have a service in my Android app that has to do some actions once every 5 minutes.

In order to achieve this I've tried to run TimerTask through Timer.scheduleAtFixedRate method, but the rate appeared not to be fixed at all - after some hours of running ticks stop, then (after some hours!) timer wakes up and instantly fires a series of couple of dozens ticks... According to the reference its a normal behaviour:

If an execution is delayed for any reason (such as garbage collection or other background activity), two or more executions will occur in rapid succession to "catch up."

so I had to look for another solution.

Next I've tried ScheduledExecutorService and it's scheduleAtFixedRate method, following the answer from scheduleAtFixedRate executes fast . It also doesn't fully resolve the issue - I observe the same freezes, though they are shorter (up to an hour).

My current code is simple:

    scheduler = Executors.newSingleThreadScheduledExecutor();
    scheduler.scheduleAtFixedRate(new Runnable() {
            @Override
            public void run() {
                Log.d(LOG_TAG, "Schedule run");

                mHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        Log.d(LOG_TAG, "Call timer");

                        serviceHelper.doAction();

                        Log.d(LOG_TAG, "Task complete");
                    }
                });
            }
        }, 0, AppConstant.NOTIFY_INTERVAL, TimeUnit.MILLISECONDS);

So, I need an advice how to add stability to the schedule (a gap of +-3 minutes is acceptable, but 10 to 30 minutes is the way too much).

Answer 1

I have a service in my Android app that has to do some actions once every 5 minutes. In order to achieve this I've tried to run TimerTask [...] Next I've tried ScheduledExecutorService

I think you are using wrong tool for the task as I'd consider AlarmManager far better choice. See docs' Scheduling Repeating Alarms , and make sure you understand the difference between exact and inexact alarms introduced in API 19 (as you definitely do not want the latter).