The Capacity Exchange Protocol
Ref: HURRAY-TR-071101 Publication Date: 19, Nov, 2007
The Capacity Exchange ProtocolRef: HURRAY-TR-071101 Publication Date: 19, Nov, 2007
This paper proposes a new strategy to integrate shared resources and precedence constraints among real-time tasks, assuming no precise information on critical sections and computation times is available. The concept of bandwidth inheritance is combined with a greedy capacity sharing and stealing policy to efficiently exchange bandwidth among tasks, minimising the degree of deviation from the ideal system's behaviour caused by inter-application blocking. The proposed Capacity Exchange Protocol (CXP) focus on exchanging extra capacities as early, and not necessarily as fairly, as possible. This loss of optimality is worth the reduced complexity as the protocol's behaviour nevertheless tends to be fair in the long run and outperforms the previous solutions in highly dynamic scenarios as demonstrated by extensive simulations.