Linux as a general-purpose operating system is designed to support the services required by most generic applications. Today, there is a new generation of real-time applications that are interactive, computation-intensive, and I/O-bound. In the past years, operating system research has addressed each of these challenges in turn. Yet frequently, when an application requires the support of all three aspects in unison, performance suffers. In particular, this is the case for multimedia-oriented applications. These applications have to meet soft real-time requirements, demand for a high data throughput, and need to interact with the user. Furthermore, they are constructed in a highly modular fashion with a multitude of concurrent and interdependent activities.

The software market offers either dedicated multimedia applications or middleware solutions, each addressing these issues at a high level: The solutions are built upon existing operating system interfaces and they rather focus on the support for specific multimedia functionalities, such as decoders, instead of providing an appropriate operation infrastructure for a wider range of applications within that area. This paper targets the integration of multimedia-oriented applications from a new angle. We improve the support for such applications by means of dedicated system services: Instead of the common process model, our execution paradigm is based on the process network model. This model is an established formalism in the field of embedded systems. We leverage the theoretic findings by implementing them into a real operating system. Additionally, we contribute dedicated buffer management and scheduling facilities by exploiting the advantages of the process network model. The implementation is realized both as a kernel-space and a user-space solution. For the kernel-space solution, we extend the Linux kernel and its system-call interface to use the full potential of kernel-internal features.

Read Full Paper (PDF Download)

 
This article was originally published on LinuxDevices.com and has been donated to the open source community by QuinStreet Inc. Please visit LinuxToday.com for up-to-date news and articles about Linux and open source.