Android thread runnable performance

问题:

I'm wondering about performance and cpu/ram requirements for 2 different methods of starting runnables

I have some code that collects sensor data every 10ms and inserts the values into a database on a background thread (using a single thread executor). Executor service is created as follows:

executor = Executors.newSingleThreadExecutor();

One way to do that would be something like...

public void onSensorChanged(SensorEvent event) {
    //get sensor values

    //insert into database
    executor.execute(new Runnable(){
        //database insert code here
    });
}

I see this method a lot in tutorials, but because I'm doing this every 10ms, it feels resource intensive as I'm creating a new object every single time a sensor value change is detected. Does this new object just get overridden every 10ms? Or is it taking up increasing amounts of RAM as new objects are created?

I have since refactored my code to look more like this:

executor = Executors.newSingleThreadExecutor();
myRunnable = new MyRunnable();

class MyRunnable implements Runnable {
    public void run() {
        //database insert code here
    }
}

public void onSensorChanged(SensorEvent event) {
    //get sensor values

    //insert into database
    executor.execute(myRunnable);
}

My thinking is that I instantiate only a single object once, instead of doing it every time sensors change. Am I correct in thinking this has lower RAM usage than the previous method? Is there a more efficient/better way to accomplish this task?

回答1:

Creating new Runnable instance every 10 ms will surely cause garbage collector to kick in more often and may impact your application performance. Your second approach i think is much better.