Research on Window-Constrained Constant Bandwidth Server to Support Adaptive QoS

Advances in computing applications in recent years have prompted the demand for more flexible scheduling models for QoS demand. The DWCS (dynamic window- constrained scheduling) is a flexible scheduling algorithm. This paper applies DWCS into the open realtime system to support QoS demand. We propose a window-constrained CBS with which the real-time system can use the characteristic of DWCS to improve the scheduling performance. Moreover, the new scheduler can provide some QoS guarantee for real-time tasks. To evaluate the performance of the new server, the two server mechanisms have been implemented on the Linux kernel. The experimental results show that the new server is better than the old server. In the end, the future research directions are discussed.