JVM实战系列之CPU100%和内存100%排查

private static List<byte[]> CACHE = new ArrayList<>(1000);
@GetMapping("/tuningTest")
public String tuningTest(){
    for (int loopTimes = 1; loopTimes < 20; loopTimes++) {
        long cacheSize = ObjectSizeCalculator.getObjectSize(CACHE);
        LOGGER.info("第 {} 次循环前, 对象已占用 {} M 内存", loopTimes, cacheSize / 1024 / 1024);
        // 每次占用5M内存
        CACHE.add(new byte[5 * 1024 * 1024]);
    }
    return "OK";
}

/**
 * 死循环
 *
 * @return
 */
@RequestMapping("/deadCycle")
public String deadCycle() {
    for (int i = 1; i > 0; i++) {
        System.out.println(i);
    }
    return "Success";
}
/**
 * 死锁
 *
 * @return
 */
@RequestMapping("/deadLock")
public String deadLock() {
    Lock lock1 = new ReentrantLock();
    //线程t1中
    new Thread(() -> {
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        while (!lock1.tryLock()) {
            System.out.println("线程1 一直自旋获取锁");
        }
        System.out.println("线程1 获取到锁 do something");
    }).start();
    // 线程2
    new Thread(() -> {
        lock1.lock();  //此时线程2 获取到锁 但是一直阻塞 导致锁无法释放
        while (true) {
        }
    }).start();
    return "Success";
}