Parallel Reservation Processing Using Software Transactional Memory

Although the necessity for parallel processing is increasing by spreading of multicore processors or Cloud, the problem peculiar to parallel processing has still faced us greatly. There are dangers of competition among data, deadlock, and livelock when we build parallel processing using low-level-locks. However, Communicating Sequential Processes(CSP) and Software Transactional Memory(STM) are available as technologies to resolve the problems. As CSP’s description is simpler, we should only describe what event will happen and which event will be interconnected. Using JCSP, we can implement a CSP model in Java. The description will be also simpler. But we will face complex code in other part of a CSP model using Java. Moreover, CSP takes a message-passing form that makes us wait when many processes access to one process. In contrast, STM takes an optimistic non-blocking parallelism form that does not make us wait. Instead of wait, a retry will occur. Therefore, we have chosen STM and we consider implementing parallel processing using Clojure. Clojure has STM as language specification, and makes our description simpler than Java, and also can use huge Java library. By explaining seat reservation processing as an example the guideline for constructing parallel processing using Clojure STM is shown