A Library Implementation of POSIX Threads （一个图书馆POSIX线程的实现）.pdf

A Library Implementation of POSIX Threads under UNIX Frank Mueller1 – Florida State University ABSTRACT Recently, there has been an effort to specify an IEEE standard for portable operating systems for open systems, called POSIX. One part of it, the POSIX 1003.4a threads extension (Pthreads for short) [12], describes the interface for light-weight threads that rely on shared memory and have a smaller context frame than processes. This paper describes and evaluates the design and implementation of a library of Pthreads calls that is solely based on UNIX. It shows that a library implementation is feasible and can result in good performance. This work can also be used as a comparison of the performance of other implementations, or as a prototyping, testing, and debugging system in the regular UNIX environment. Finally, some problems with the Pthreads standard are identified. Introduction more detailed discussion of the design and imple- mentation. Finally, measurements and their evalua- Light-weight threads are independent threads of tions, unresolved problems with the standard, future control within a regular process that share global work, and summary follow. data (global variables, files, etc.) but maintain their own stack, local variables, and program counter.