@Override
        public Thread newThread(Runnable runnable) {
            final Thread result = new Thread(runnable, "fifo-pool-thread-" + threadNum) {
                @Override
                public void run() {
                    android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_BACKGROUND);
                    super.run();
                }
            };
            threadNum++;
            return result;
        }
A {@link ThreadFactory} that builds threads with priority
{@link android.os.Process#THREAD_PRIORITY_BACKGROUND}.
core/src/main/java/com/bumptech/glide/load/engine/executor/FifoPriorityThreadPoolExecutor.java