In the spring of 1979, I had seen a number of papers on implementing Scheme directly on VLSI chips. This led me to ask what were the minimal extensions to Scheme necessary to build an operating system for such a chip. It appeared that three facilities were necessary: data protection, process saving, and elementary exclusion. Although exclusion clearly required support from the underlying machin...

The smart grid revolution has only been possible, thanks to the development and proliferation of meters. increasingly growing computing capabilities for Internet Things devices have made it possible data be processed directly from where is produced; this called edge computing. Edge allowing become intelligent solve problems that make electricity consumption more efficient environmentally friend...

Meaningful Quality of Service (QoS) guarantees for`delay sensitive' networked applications must be end-to-end. This paper presents an experimental study of applications using computer workstation end-points. For the application experiments, the variables under study were the degree of multiprocessing, the transport protocol used (UDP or TCP), the process structure used by the application, and t...

This paper examines the performance benefits of employing multicast communication and application-level multithreading in the Brazos software distributed shared memory (DSM) system. Application-level multithreading in Brazos allows programs to transparently take advantage of available local multiprocessing. Brazos uses multicast communication to reduce the number of consistency-related messages...

Concurrent computing environments based on loosely coupled networks have proven effective as resources for multiprocessing. Experiences with and enhancements to PVM (Parallel Virtual Machine) are described in this paper. PVM is a software system that allows the utilization of a heterogeneous network of parallel and serial computers as a single computational resource. This report also describes ...

With today’s rise of multi-core processors in the desktop market and in common server systems, concurrency becomes a ubiquitous challenge in software development. Concurrency allows the improvement of software performance by exploiting available processor cores. However, possible performance gained by concurrency can be limited by software bottlenecks or inherently sequential parts of the appli...

QEMU is an open source emulator for complete PC systems. In addition to emulating a processor, QEMU permits emulation of all necessary subsystems, such as networking and video hardware. It also permits emulation of advanced concepts, such as symmetric multiprocessing systems (up to 255 CPUs) and other processor architectures, such as ARM or PowerPC. This article explores QEMU and its architectu...