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This paper describes how Dynamic Window-Constrained Scheduling (DWCS) can guarantee real-time service to packets from multiple streams with different performance objectives. We show that: (1) DWCS can guarantee that no more than x packets miss their deadlines for every y consecutive packets requiring service, as long as the minimum aggregate bandwidth(More)
This paper describes an algorithm, called Dynamic Window-Constrained Scheduling (DWCS), designed to meet the service constraints on packets from multiple , network-bound media streams with different performance objectives. Using only two attributes, a deadline and a loss-tolerance per packet stream, DWCS: (1) can limit the number of late packets over finite(More)
This paper describes an algorithm for scheduling packets in real-time multimedia data streams. Common to these classes of data streams are service constraints in terms of bandwidth and delay. However, it is typical for real-time multimedia streams to tolerate bounded delay variations and, in some cases, finite losses of packets. We have therefore developed(More)
This paper presents HiRes, a system structured around predictable, hierarchical resource management (HRM). Applications and different subsystems use customized resource managers that control the allocation and usage of memory, CPU, and I/O. This increased resource management flexibility enables subsystems with different timing constraints to specialize(More)
Customizable/extensible base system upon which wide range of systems can be built with application-specific services and abstractions System dependability challenges code complexity complicate testing and verification focus on fault tolerance services provided by 3rd party, untrusted developers System policies and abstractions defined in separate components
This paper outlines the design of 'Quest-V', which is implemented as a collection of separate kernels operating together as a distributed system on a chip. Quest-V uses virtualization techniques to isolate kernels and prevent local faults from affecting remote kernels. This leads to a high-confidence multikernel approach, where failures of system(More)
As software systems are becoming increasingly complex, the likelihood of faults and unexpected behaviors will naturally increase. Today, mobile devices to large-scale servers feature many millions of lines of code. Compile-time checks and offline verification methods are unlikely to capture all system states and control flow interactions of a running(More)
This paper presents an asynchronous event handling mechanism for real-time applications that leverages existing system services in COTS systems. In our implementation , event dispatching is initiated within bottom-half interrupt handling routines, in order to support predictable, safe, and efficient event handling functionality at user-level. We compare our(More)
This paper is centered around the design of a thread-and memory-safe language, primarily for the compilation of application-specific services for extensible operating systems. We describe various issues that have influenced the design of our language, called Cuckoo, that guarantees safety of programs with potentially asynchronous flows of control.(More)