Decreasing the Locks by Isolating the Concurrent Execution in Microprotocol Framework.

We propose the methodology to reduce the range of isolating the event flows by concurrent execution in micro protocol framework which is used in developing distributed system. A micro protocol is a software component to reduce the complexity of designing, developing and testing distributed systems. A distributed system is decomposed into micro protocols based on communication which provides the reusable and flexible composition. There are two types of event flows in a distributed system which are "send", "broadcast" and "receive" event among remote nodes and local node. There is concurrency not only between "send" and "receive" events but also among "send" events and among "receive" events. There is a potential race condition in this kind of distributed environment. Due to providing dynamic composition, the complexity is high in the existing micro protocol framework which supports concurrent execution. Although there is software transactional memory (STM) of which the methodology supports the concurrency, locking resources is necessary. Since the micro protocol is a resource, it implies that locking all related micro protocols is necessary too. In the complex composition of micro protocols, since there are some cases that several microprotols take part in only one event flow, there are few concurrent execution flows due to locking several micro protocols. We propose micro protocol framework which increases concurrent execution as many as possible by means of locking only the possible areas of race condition by concurrency. We evaluate our selective locking methodology compared to locking all micro protocols. [ABSTRACT FROM PUBLISHER]