有没有字节工牌，Java并发安全的根本原因都得懂

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中增加了高速缓存，来平衡其与内存的速度差异。操作系统通过增加进程、线程，以便与最大可能分时复用 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看上去是执行了一条指令实际上包含了三条指令。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"（1）首先，需要把变量","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"count","attrs":{}}],"attrs":{}},{"type":"text","text":"从内存加载到工作线程的工作内存中；","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"（2）加载后在工作内存中执行","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"+1","attrs":{}}],"attrs":{}},{"type":"text","text":"操作；","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"（3）最后，将计算结果写入内存。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"如上文所说的，由于计算机的大部件之间存在数据处理速度差异，处理一项任务时往往是","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"CPU","attrs":{}}],"attrs":{}},{"type":"text","text":"在等待其他部件完成后才进行后续的操作，为了提高","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"CPU","attrs":{}}],"attrs":{}},{"type":"text","text":"的工作效率，可以在","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"CPU","attrs":{}}],"attrs":{}},{"type":"text","text":"等待期间让出CPU使用权，让","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"CPU","attrs":{}}],"attrs":{}},{"type":"text","text":"去处理其他事情，这就是所谓的分时复用。那么在","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"Java","attrs":{}}],"attrs":{}},{"type":"text","text":"多线程场景下，必定也会发生线程切换，如下图所示，由于","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"count++","attrs":{}}],"attrs":{}},{"type":"text","text":"不具备运算的原子性，导致了线程在运行过程中发生线程切换，最终导致输出结果与预期不一致。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/05/051811ddf962e92831b56a97ee49f517.png","alt":null,"title":"","style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"我们把一个或者多个操作在 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