tine对此变量的写。 修改一个同时被多个goroutine并发访问的变量的时候，需要串行化访问。通过channel或者其它同步原语实现串行化访问。 ’ alt=‘OCR图片’/> happen-before Memory Order Guarantee 单个goroutine内 读写执行的顺序和程序定义顺序一致乱序执行不影响程序的行为 happen before 内存操作的偏序(partial after a a does not happen before b, and does not happen after b, a和b同时发生 ’ alt=‘OCR图片’/> happen-before strict partial order transitive(传递性): $ \forall a,b,c $ ,if a $ \rightarrow b $ and b $ \rightarrow $ \forall a,b $ ,where $ a\neq b $ ,if $ a\to b $ then $ b\rightarrow a $ ’ alt=‘OCR图片’/> happen-before A read r of a variable v is allowed to observe a write w to v if both of the following hold: