Technology scaling has enabled the number of cores within a System on Chip (SoC) to increase significantly. Globally Asynchronous Locally Synchronous (GALS) systems using Dynamic Voltage and Frequency Scaling (DVFS) operate each of these cores on distinct and dynamic clock domains. The main communication method between these cores is increasingly more likely to be a Network-on-Chip (NoC). Typic...

Energy consumption has become a major concern for all computing systems, from servers in data-centres to mobile phones. Processor manufacturers have reacted to this by implementing power-management mechanisms in the hardware and researchers have investigated how operating systems can make use of those mechanisms to minimise energy consumption. Much of this research has focused on a single class...

The increasing popularity of DVFS (dynamic voltage frequency scaling) schemes for portable low power applications demands highly efficient on-chip DC-DC converters. The primary aim of this work is to enable increased efficiency of on-chip DC-DC conversion for near-threshold operation of multicore chips. The idea is to supply nominal (high) off-chip voltage to the cores which are then “voltage-s...

In real-time systems, it is required to complete all work on a timely basis. There are mainly two types of real time systems: hard real-time systems (HRT) and soft-real time (SRT) systems. In hard real-time systems, a missed deadline is considered a system failure; in soft real-time systems some deadlines may be missed. The aim of real-time scheduling analysis is to ensure a sequence of jobs me...

Dynamic voltage and frequency scaling of the CPU has been identified as one of the most effective ways to reduce energy consumption of a program. This paper discusses a compilation strategy that identifies scaling opportunities without significant overall performance penalty. Simulation results show CPU energy savings of 3.97%23.75% for the SPECfp95 benchmark suite with a performance penalty of...

Nos últimos anos tem havido uma crescente utilização de sistemas embarcados devido os avanços da tecnologia, a redução dos custos dos equipamentos eletrônicos e, principalmente, a popularização dos dispositivos móveis. Muitos desses sistemas implementam políticas de baixo consumo de energia para prolongar ao máximo a sua autonomia, pois possuem uma quantidade reduzida de recursos e a grande mai...

We consider a task graph to be executed on a set of processors. We assume that the mapping is given, say by an ordered list of tasks to execute on each processor, and we aim at optimizing the energy consumption while enforcing a prescribed bound on the execution time. Although it is not possible to change the allocation of a task, it is possible to change its speed. Rather than using a local ap...

Compiler-directed dynamic voltage scaling (DVS) is an effective low-power technique in real-time applications, where compiler inserts voltage scaling points in a real-time application, and supply voltage and clock frequency are adjusted to the relationship between the remaining time and the remaining workload at each voltage scaling point. Greedy dynamic voltage scaling is one of the voltage ad...

Energy consumption has been a critical issue in high-performance computing systems, such as clusters and data centers. An existing technique to reduce energy consumption of applications is dynamic voltage/frequency scaling (DVFS). In this paper, we present a novel algorithm called EASLA for energy aware scheduling of precedence-constrained applications in the context of Service Level Agreement ...

A Run-Time Management system for many-core architecture is aware of application requirements and able to save energy by sacrificing performance when it will have negligible impact on user experience. This paper outlines the application of a process for development of a run-time management system that integrates a range of modelling, validation, verification and generation tools at appropriate s...