利用信号量机制解决操作系统中的同步与互斥问题

Solving the Problem of Sync and Mutex in Operating System by Semaphore Mechanism

在多道程序环境下,由于进程共享资源和进程之间的合作,使得并发执行的多个进程间可能产生互斥或同步的相互制约关系,如果不采取措施来保证这种制约或依赖关系,不仅影响系统效率,而且还会导致结果的不可再现性。为此,现代操作系统都在内核中设有进程的同步机制,以控制并发执行的各进程间能更有效地共享资源和相互合作,同时使并发进程的执行具有可再现性。信号量机制是操作系统中协调各进程同步与互斥的一种常用工具。

Because of the corporation between the process of sharing resources and processes in the multiprogramming environment ,the mutual restrictive relationship of mutually exclusive synchronization or repulsion effect will be produced in the multiple process concurrent execution. If no measures are taken to ensure this constraint or dependency,not only affects the system efficiency, but also lead to non - reproducibility of results. Therefore, modern operating system has a process in kernel synchronization mechanism in order to control concurrent execution among the various processes to more effectively share resources and cooperate with each other, while making the implementation of a concurrent process reproducibility. Semaphore mechanisms is a common tool, which coordinate the process of synchronization and mutual exclusion, in the operating system.