一种并发PASCAL语言的设计与实现

本文论述了作者设计的一种并发PASCAL语言,语言中采用了作者提出的“可更换式进程调度”思想,使本语言不但能满足不同用户对调度策略的需求,同时还可以使本系统开销保持在很低的水平.“可更换式进程调度”的含义是:在并发PASCAL语言的进程调度中,不是采用传统的固定的调度算法模式,而是允许程序员按照不同需求,使用不同算法的进程调度内核程序.

Design and Implementation of a Concurrent PASCAL

In traditional concurrent PASCAL Language, a kind of fixed algorithm is usually adopted to perform process dispatch. Such dispatch model appears to be unable to satisfy all the needs of different users. In order to overcome this shortcoming, the authors present a new concurrent PASCAL based on "Changeable Process Dispatch". The meaning of "Changeable Process Dispatch" is: process dispatch modules corresponding to a number of different algorithms are available so as to allow the user to select the most suitable one. "Changeable Process Dispatch" has already been adopted in a concurrent PASCAL compiler designed and constructed by the authors. Running of the authors' concurrent PASCAL compiler shows that " Changeable Process Dispatch" works satisfactorily. Compared with traditional fixed process dispatch model, it brings the following advantages: 1. Flexibility is greatly enhanced since the user has many process dispatch modules at his disposal and special needs of any particular situation can be better satisfied. 2. The effectiveness of the running of different dispatch modules can be compared by programmer. 3. New process dispatch module can be easily added and obsolete old one can be easily removed. 4. The system overhead can be reduced.