Contract based management of the memory resource

Resource reservation has been widely used in many realtime systems to guarantee the proper access to the system resources. Despite that being the memory a key resource, it has attracted little attention in the specific area of realtime systems. In order to use dynamic memory in real-time systems, two fundamental problems have to be settled: allocation and deallocation in bounded time, and the fragmentation problem. Recent research results have removed the unbounded timing behaviour of the dynamic memory allocation. TLSF is a fast and constant time memory allocator. Although the fragmentation is still an open research problem, we present a deep and comparative analysis showing that it has several characteristics in common with the well-known WCET analysis. In this paper, we present a contract based framework for handling dynamic memory in real-time systems. The framework provides both: i) timing guarantee for dynamic memory allocation and deallocation operations, and ii) spatial guarantee by using a flexible contract negotiation model.