线程局部存储（thread-local storage, TLS）是一个使用很方便的存储线程局部数据的系统。利用TLS机制可以为进程中所有的线程关联若干个数据，各个线程通过由TLS分配的全局索引来访问与 自己关联的数据。这样，每个线程都可以有线程局部的静态存储数据。-Thread-local storage (the thread-local storage TLS) is a very convenient store thread-local data systems. TLS mechanism for all threads in the process associated with a number of data, each thread to access the data associated with their global index assigned by the TLS. In this way, each thread can have a thread-local static storage of data.