ConRS: A Requests Scheduling Framework for Increasing Concurrency Degree of Server Programs

Server programs always store a great deal of data and respond to plenty of requests in a short time. Most server programs are highly concurrent. Testing concurrent programs is difficult and costly because of their non-determinism. Researches have shown that increasing the degree of concurrency is more effective for testing process. This paper uses synchronization-pair and data race to quantify the degree of concurrency. The more synchronization-pairs and data races in a trace are, the higher concurrency degree is. A requests scheduling framework ConRS is proposed in this paper to reschedule requests in an existing test case and make the program "more concurrent". Compared with server stress testing tools, ConRS includes more categories of requests. Compared with coverage-guided bug detectors and data race detectors, ConRS are lower overhead and easier to understand. The experiments on MySQL database server show the effectiveness of ConRS. The synchronization-pairs and data races of test cases have been increased by at least 10% and 30% respectively after applying ConRS.