public static final int CORE_NOTIFICATION_THREADS = 4;
public static final int MAX_NOTIFICATION_THREADS = 32;
+ // block caller thread after MAX_NOTIFICATION_THREADS + MAX_NOTIFICATION_QUEUE_SIZE pending notifications
+ public static final int MAX_NOTIFICATION_QUEUE_SIZE = 10;
public static final int NOTIFICATION_THREAD_LIFE = 15;
private static ListeningExecutorService NOTIFICATION_EXECUTOR = null;
public static synchronized final ListeningExecutorService getDefaultNotificationExecutor() {
if (NOTIFICATION_EXECUTOR == null) {
- // Overriding the queue since we need an unbounded queue
- // and threadpoolexecutor would not create new threads if the queue is not full
- BlockingQueue<Runnable> queue = new LinkedBlockingQueue<Runnable>() {
+ // Overriding the queue:
+ // ThreadPoolExecutor would not create new threads if the queue is not full, thus adding
+ // occurs in RejectedExecutionHandler.
+ // This impl saturates threadpool first, then queue. When both are full caller will get blocked.
+ BlockingQueue<Runnable> queue = new LinkedBlockingQueue<Runnable>(MAX_NOTIFICATION_QUEUE_SIZE) {
@Override
public boolean offer(Runnable r) {
- if (size() <= 1) {
- // if the queue is empty (or has just 1), no need to rampup the threads
- return super.offer(r);
- } else {
- // if the queue is not empty, force the queue to return false.
- // threadpoolexecutor will spawn a new thread if the queue.offer returns false.
- return false;
- }
+ // ThreadPoolExecutor will spawn a new thread after core size is reached only if the queue.offer returns false.
+ return false;
}
};
try {
executor.getQueue().put(r);
} catch (InterruptedException e) {
- e.printStackTrace();
+ Thread.currentThread().interrupt();// set interrupt flag after clearing
+ throw new IllegalStateException(e);
}
}
});