Modular software architecture for flexible reservation mechanisms on heterogeneous resources

Abstract

Management, allocation and scheduling of heterogeneous resources for complex distributed real-time applications is a challenging problem. Timing constraints of applications may be fulfilled by a proper use of real-time scheduling policies, admission control and enforcement of timing constraints. However, it is not easy to design basic infrastructure services that allow for an easy access to the allocation of multiple heterogeneous resources in a distributed environment.In this paper, we present a middleware for providing distributed soft real-time applications with a uniform API for reserving heterogeneous resources with real-time scheduling capabilities in a distributed environment. The architecture relies on standard POSIX OS facilities, such as time management and standard TCP/IP networking services, and it is designed around CORBA, in order to facilitate modularity, flexibility and portability of the applications using it. However, real-time scheduling is supported by proper extensions at the kernel-level, plugged within the framework by means of dedicated resource managers. Our current implementation on Linux supports reservation of CPU, disk and network bandwidth. However, additional resource managers supporting alternative real-time schedulers for these resources, as well as additional types of resources, may be easily added.We present experimental results gathered on both synthetic applications and a real multimedia video streaming case study, showing advantages deriving from the use of the proposed middleware. Finally, overhead figures are reported, showing sustainability of the approach for a wide class of complex, distributed, soft real-time applications.

Designing end-to-end resource reservations in predictable distributed embedded systems

“…Nevertheless, very few works have addressed the reservation of resources at the distributed system level, where the resources include both processor and network. Some of these works consider soft real-time systems targeting multimedia applications such as Sojka et al (2011) and Dermler et al (1996). An adaptive Quality of Service (QoS) control is developed in Cucinotta and Palopoli (2010) to control the reservation during run-time.…”

POET: a portable approach to minimizing energy under soft real-time constraints

“…Rajkumar et al propose a general framework (with system specific implementation) for allocating resources to achieve real-time requirements, but this approach is not energy-aware [41]. Sojka et al proposed a portable middleware layer for allocating resources to meet soft real-time constraints, but this system does not minimize energy [49]. ControlWare is another middleware approach that uses control theory to meet qualityof-service constraints, but does not address energy concerns [56].…”

“…In summary, POET is most related to prior approaches that abstract resource management into a middleware or runtime, like [20,41,49,56]. POET is unique in its energy awareness, in its design for portability, and the incorporation of a true minimal-energy resource allocation algorithm.…”

A Probabilistic Graphical Model-based Approach for Minimizing Energy Under Performance Constraints

“…For example, many systems employ control theoretic designs which couple offline model building with online feedback control [9,24,27,36,39,46,47,51,57,61]. Over a narrow range of applications the combination of offline learning and control works well, as the offline models capture the general behavior of the entire class of application and require negligible online overhead.…”