An adaptive buffer management algorithm for enhancing dependability and performance in mobile-object-based real-time computing

In an ORC (object oriented real time computing) environment, it is important to reduce message retransmissions during message passing because these retransmissions cause significant time delay, and this makes it difficult to achieve the necessary timeliness. A cause of retransmission is message loss due to buffer overflow at the reception side. Here a P+I+D (P for proportional, I for integral and D for derivative) adaptive buffer control algorithm is proposed to prevent such possible overflow. The I control depends on the Convergence Algorithm (CA), which is a stable and efficient IEPM (Internet End-to-End Performance Measurement) tool that predicts the mean message roundtrip time (RTT) of a communication channel quickly and accurately. The P+I+D algorithm was tested under different conditions in a mobile ORC (MORC) environment where mobile agents collaborate freely over the Internet. The different test results confirm that the proposed P+I+D approach is indeed effective for preventing buffer overflow