Understanding High Concurrency_Preface

     High concurrency is no longer a hot word, but it is not easy to use it well. In many cases, if it is not used properly, it is very easy to have the opposite effect. In this series, I will systematically share with you the technical points of high concurrency. Its specific technical points include the following:
     1. My understanding of concurrent programming
     2. The principle and usage of synchronized
     3. The usage of explicit locks
     4. Lock optimization techniques
     5. _wait/notify
     of thread communication 6. _semaphore of thread communication Semaphore
     7. _countDownLatch for
     thread communication 8. _cyclicBarrier for thread communication
     9. Future, Callable implementation principle and usage
    10. Threadlocal principle and usage
    11. Volatile principle and usage
    12. Talk about Amdahl's law
    13. Concurrency Collection of _CopyOnWriteArrayList
    14. Concurrent collection of _ArrayBlockingQueue
    15. Concurrent collection of _LinkBlockingQueue
    16. Concurrent collection of _ConcurrentMap
    17. Usage of fork/join framework
    18. Using redis to implement distributed locks
    19. Using zookeeper to implement distributed locks
    20. How to monitor the running status of threads
    21. JVM memory model