Research And Applications Of Program Control Technology Based On Distributed System

A judge system accepts user's program via network, runs it on the server, and checks whether the results are correct. Running user's program on the server may cause potential security issues, so there must be a way to monitor and control user's program. As the core technology of the online judge system, program control must be secure and efficient. This article discusses how to monitor and control a program under Linux operating system. There are two ways to monitor and control user's problem. One is to modify system interrupt vector table, and the other one is to use ptrace system call. In order to solve the efficiency issue, this article introduces a solution based on distributed system. Distributed online judge system is efficient, reliable, and extendable. At last, based on the distributed program control technology, we implemented the new Zhejiang University Online Judge System. Compared with the old online judge, the new online judge is more powerful.