Effective runtime resource management using linux control groups with the BarbequeRTRM framework

The extremely high technology process reached by silicon manufacturing (smaller than 32nm) has led to production of computational platforms and SoC, featuring a considerable amount of resources. Whereas from one side such multi- and many-core platforms show growing performance capabilities, from the other side they are more and more affected by power, thermal, and reliability issues. Moreover, the increased computational capabilities allows congested usage scenarios with workloads subject to mixed and time-varying requirements. Effective usage of the resources should take into account both the application requirements and resources availability, with an arbiter, namely a resource manager in charge to solve the resource contention among demanding applications. Current operating systems (OS) have only a limited knowledge about application-specific behaviors and their time-varying requirements. Dedicated system interfaces to collect such inputs and forward them to the OS (e.g., its scheduler) are thus an interesting research area that aims at integrating the OS with an ad hoc resource manager. Such a component can exploit efficient low-level OS interfaces and mechanisms to extend its capabilities of controlling tasks and system resources. Because of the specific tasks and timings of a resource manager, this component can be easily and effectively developed as a user-space extension lying in between the OS and the controlled application. This article, which focuses on multicore Linux systems, shows a portable solution to enforce runtime resource management decisions based on the standard control groups framework. A burst and a mixed workload analysis, performed on a multicore-based NUMA platform, have reported some promising results both in terms of performance and power saving

Extending a run-time resource management framework to support OpenCL and heterogeneous systems

From Mobile to High-Performance Computing (HPC) systems, performance and energy efficiency are becoming always more challenging requirements. In this regard, heterogeneous systems, made by a general-purpose processor and one or more hardware accelerators, are emerging as affordable solutions. However, the effective exploitation of such platforms requires specific programming languages, like for instance OpenCL, and suitable run-time software layers. This work illustrates the extension of a run-time resource management (RTRM) framework, to support the execution of OpenCL applications on systems featuring a multi-core CPU and multiple GPUs. Early results show how this solution leads to benefits both for the applications, in terms of performance, and for the system, in terms of resource utilization, i.e. load balancing and thermal leveling over the computing devices

Современное состояние электрификации России

В статье показано, что современное развитие электрификации РФ в сопоставлении с государствами, входящими в G8, очевидно недостающее. При этом есть большой потенциал электросбережения в секторах экономики. Потребление электроэнергии населением существенно находится в зависимости от значения их денежных доходов и темпов роста тарифов на электричество

Predictive Models for Multimedia Applications Power Consumption Based on Use-Case and OS Level Analysis

Power management at any abstraction level is a key issue for many mobile multimedia and embedded applications. In this paper a design workflow to generate system-level power models will be presented, tailored to support quantitative runtime power optimization policies to be implemented within an operating system. The approach we followed to derive power models is strongly use-case oriented. Starting from a comprehensive general and accurate model of a representative architecture for embedded applications (including a multi core MPSoC, accelerators, interfaces and peripherals), a methodology to derive compact models is presented, based upon the distinctive characteristics of the selected use cases. The methodology to generate such model, whose exploitation is foreseen within a power manager working at the OS level, is the focus of the paper. The value and accuracy of the approach is quantitatively and statistically justified through extensive experiments carried out on a development board designed for multimedia applications

A Hierarchical Distributed Control for Power and Performances Optimization of Embedded Systems

Power and resource management are key goals for the success of modern battery-supplied multimedia devices. This kind of devices are usually based on SoCs with a wide range of subsystems, that compete in the usage of shared resources, and offer several power saving capabilities, but need an adequate software support to exploit such capabilities. In this paper we present Constrained Power Management (CPM), a cross-layer formal model and framework for power and resource management, targeted to MPSoC-based devices. CPM allows coordination and communication, among applications and device drivers, to reduce energy consumption without compromising QoS. A dynamic and multi-objective optimization strategy is supported, which has been designed to have a negligible overhead on the development process and at run-time

A RTRM proposal for multi/many-core platforms and reconfigurable applications

Emerging multi/many-core architectures, targeting both HPC and mobile devices, increase the interest for self- adaptive systems, where both applications and computational resources could smoothly adapt to the changing of the working conditions. In these scenarios, an efficient Run-Time Resource Manager (RTRM) framework can provide a valuable support to identify the optimal trade-off between the QoS requirements of the applications and the time varying resources availability. This paper introduces a new approach to the development of a system-wide RTRM featuring: a) a hierarchical and distributed control, b) the exploitation of design-time information, c) a rich multi-objective optimization strategy and d) a portable and modular design based on a set of tunable policies. A first version of the framework is already available as an Open Source project, targeting a NUMA architecture and a new generation Multi/Many-core platform. First tests show, benefits for the execution of parallel applications, the scalability of the proposed multi-objective resources partitioning strategy, and the sustainability of the overheads introduced by the framework

Run-time Resource Management at the Operating System Level

Available hardware platforms provide the applications with an extended set of physical resources, as well as a well defined set of power and performance optimization mechanisms (i.e., hardware control knobs). The software stack, meanwhile, is responsible of taking direct advantage of these resources, in order to meet application functional and non-functional requirements. The support from the Operating System (OS) is of utmost importance, since it gives opportunity to optimize the system as a whole. Purpose of this chapter is to introduce the reader to the challenge of managing physical and logical resources in a complexmulti- and many-core architectures, focussing on emerging MPSoC platforms

A Low-Overhead Heuristic for Mixed Workload Resource Partitioning in Cluster-Based Architectures

The execution of multiple multimedia applications on a modern Multi-Processor System-on-Chip (MPSoC) rises up the need of a Run-Time Management (RTM) layer to match hardware and application needs. This paper proposes a novel model for the run-time resource allocation problem taking into account both architectural and application standpoints. Our model considers clustered and non-clustered resources, migration and reconfiguration overheads, quality of service (QoS) and application priorities. A near optimal solution is computed focusing on spatial and computational constraints. Experiments reveal that our first implementation is able to manage tens of applications with an overhead of only fews milliseconds and a memory footprint of less than one hundred KB, thus suitable for usage on real systems