Access Control for Adaptive Reservations on Multi-User Systems

Palopoli

2010

IEEE Trans. Comput.

We consider soft real-time applications organised as pipelines of tasks using resources of different type (communication, computation, storage). The applications are assumed to be periodically triggered and the different tasks communicate by unidirectional buffers. The problem we cope with is how to effectively share the resources so that some specified Quality of Service (QoS) requirements are met. The QoS considered here is tightly related to the end-to-end temporal behaviour of the application. To compensate for time-varying resource requirements, we advocate a distributed control approach whereby the scheduling parameters of each task are tuned depending on the temporal behaviour of the application measured by appropriate sensors. The use of real-time scheduling strategies enables a mathematically safe control design, in which the QoS requirements are translated into formal control goals, and formal proofs are provided on the ability of the controller to fulfil these goals. We also offer extensive simulations that validate the approach for multimedia applications.

Section: F Scalabilitymentioning

confidence: 99%

QoS Control for Pipelines of Tasks Using Multiple Resources

Palopoli

2010

IEEE Trans. Comput.

“…The Interface Module allows user-space applications to request reservations of the CPU, letting all of the posted requests go through the Supervisor Module. The latter implements an appropriately designed access control model (Cucinotta 2008), by means of which AQuoSA is available to nonprivileged users under a security policy that may be configured by the system administrator. Most of other real-time extensions to Linux, instead, allow only privileged users to take advantage of the available real-time functionality.…”

Section: Adaptive Quality Of Service Architecture (Aquosa)mentioning

confidence: 99%

Real-Time Attributes in Operating Systems

Advances in Systems Analysis, Software Engineering, and High Performance Computing

Gogouvitis

Self Cite

General-Purpose Operating Systems (GPOSes) are being used more and more extensively to support interactive, real-time and distributed applications, such as found in the multimedia domain. In fact, the wide availability of supported multimedia devices and protocols, together with the wide availability of libraries and tools for handling multimedia contents, make them an almost ideal platform for the development of this kind of complex applications. However, contrarily to Real-Time Operating Systems, General-Purpose ones used to lack some important functionality that are needed for providing proper scheduling guarantees to application processes. Recently, the increasing use of GPOSes for multimedia applications is gradually pushing OS developers towards enriching the kernel of a GPOS so as to provide more and more real-time functionality, thus enhance the performance and responsiveness of hosted time-sensitive applications. In this chapter, an overview is performed over the efforts done in the direction of enriching GPOSes with real-time capabilities, with a particular focus on the Linux OS. Due to its open-source nature and wide diffusion and availability, Linux is one of the most widely used OSes for such experimentations.

“…The AQuoSA framework (Luigi Palopoli et al, 2008), (OCERA -Open Components for Embedded Real-time Applications), (OCERA Project Deliverable D1.1 -RTOS), (S. Oikawa et al, 1999), Error: Reference source not foundenhances a standard GNU/Linux system with scheduling strategies based on the Resource Reservation techniques (Tommaso Cucinotta, 2008).…”

Section: The Aquosa Apimentioning

confidence: 99%

Programming Interfaces for Realtime and Cloud-Based Computing

Katsaros

Advances in Systems Analysis, Software Engineering, and High Performance Computing

Self Cite

The appearance of different business roles according to this classification, potentially with differing interests, introduces new challenges with regard to the tools and mechanisms put in place in order to enable the efficient provisioning of services. Security, Quality of Service (QoS) assurance, and real-time capabilities are just a few issues that the providers are trying to tackle and integrate within the new products and services that they offer. In this chapter, we make an overview of the approaches that aim to APIs for real-time computing. In the first part of this chapter, several Real-Time Application Interfaces will be presented and compared. After that, we will document the state-of-the-art regarding the Cloud APIs available and analyze the architecture and the technologies that they support.