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Application domains such as multimedia, databases, and parallel computing, require operating system services with high performance and high functionality. Existing operating systems provide fixed interfaces and implementations to system services and resources. This makes them inappropriate for applications whose resource demands and usage patterns are(More)
When user-level threads are built on top of traditional kernel threads, they can exhibit poor performance or even incorrect behavior in the face of blocking kernel operations such as I/O, page faults, and processor preemption. This problem can be solved by building user-level threads on top of a new kernel entity, the scheduler activation. The goal of the(More)
CPU scheduling and admission testing for multimedia applications have been extensively studied, and various solutions have been proposed using assorted simplifying assumptions. However , we believe that the complexity and dynamic behavior of multimedia applications and systems make static solutions hard to apply in real-world situations. We are analyzing(More)
1 Introduction CPU scheduling in conventional general purpose operating systems performs poorly for real-rate applications, applications with specific rate or throughput requirements in which the rate is driven by real-world demands. Examples of real-rate applications are software modems, web servers, speech recognition, and multimedia players. These kinds(More)
<italic>We describe Environmental Observation and Forecasting Systems (EOFS), a new class of large-scale distributed system designed to monitor, model, and forecast wide-area physical processes such as river systems. EOFS have strong social relevance in areas such as education, transportation, agriculture, natural resource planning and disaster response. In(More)
The Mach external pager interface allows applications to supply their own routines for moving pages to and from second-level store. Mach doesn't allow applications to choose their own page replacement policy, however. Some applications have access patterns that may make least recently used page replacement inappropriate. In this paper, we describe an(More)
Application domains such as multimedia, databases, and parallel computing, require operating system services with high performance and high functionality. Existing operating systems provide xed interfaces and implementations to system services and resources. This makes them inappropriate for applications whose resource demands and usage patterns are poorly(More)
  • Scott Cdr, Heller, +5 authors Read
  • 2006
A consensus is growing that the Department of Defense's vision of a future Global Information Grid will be built using architecture that takes advantage of Web services and uses standard Internet protocols, interchangeable components, and commercially available hardware and software wherever possible. This article describes the features and architecture of(More)
This paper describes the design and implementation of a real-time, streaming, Internet video and audio player. The player has a number of advanced features including dynamic adaptation to changes in available bandwidth, latency and latency variation; a multi-dimensional media scaling capability driven by user-specified quality of service (QoS) requirements(More)
Specialization has been recognized as a powerful technique for optimizing operating systems. However, specialization has not been broadly applied beyond the research community because current techniques based on manual specialization, are time-consuming and error-prone. The goal of the work described in this paper is to help operating system tuners perform(More)