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2011 International Green Computing Conference and Workshops最新文献

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Many-core key-value store 多核键值存储
Pub Date : 2011-07-25 DOI: 10.1109/IGCC.2011.6008565
Mateusz Berezecki, E. Frachtenberg, Mike Paleczny, K. Steele
Scaling data centers to handle task-parallel work-loads requires balancing the cost of hardware, operations, and power. Low-power, low-core-count servers reduce costs in one of these dimensions, but may require additional nodes to provide the required quality of service or increase costs by under-utilizing memory and other resources. We show that the throughput, response time, and power consumption of a high-core-count processor operating at a low clock rate and very low power consumption can perform well when compared to a platform using faster but fewer commodity cores. Specific measurements are made for a key-value store, Memcached, using a variety of systems based on three different processors: the 4-core Intel Xeon L5520, 8-core AMD Opteron 6128 HE, and 64-core Tilera TILEPro64.
扩展数据中心以处理任务并行的工作负载需要平衡硬件、操作和电源的成本。低功耗、低核数的服务器在这些方面中的一个方面降低了成本,但可能需要额外的节点来提供所需的服务质量,或者由于内存和其他资源利用率不足而增加成本。我们展示了在低时钟速率和极低功耗下运行的高核数处理器的吞吐量、响应时间和功耗,与使用更快但较少商用核的平台相比,可以表现良好。对键值存储Memcached进行了具体的测量,使用基于三种不同处理器的各种系统:4核Intel Xeon L5520、8核AMD Opteron 6128 HE和64核Tilera tile64。
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引用次数: 92
Synergistic integration of dynamic cache reconfiguration and code compression in embedded systems 嵌入式系统中动态缓存重构与代码压缩的协同集成
Pub Date : 2011-07-25 DOI: 10.1109/IGCC.2011.6008580
Hadi Hajimiri, Kamran Rahmani, P. Mishra
Optimization techniques are widely used in embedded systems design to improve overall area, performance and energy requirements. Dynamic cache reconfiguration is very effective to reduce energy consumption of cache subsystems which accounts for about half of the total energy consumption in embedded systems. Various studies have shown that code compression can significantly reduce memory requirements, and may improve performance in many scenarios. In this paper, we study the challenges and associated opportunities in integrating dynamic cache reconfiguration with code compression to retain the advantages of both approaches. Experimental results demonstrate that synergistic combination of cache reconfiguration and code compression can significantly reduce both energy consumption (65% on average) and memory requirements while drastically improve the overall performance (up to 75%) compared to dynamic cache reconfiguration alone.
优化技术广泛应用于嵌入式系统设计,以提高整体面积,性能和能源需求。在嵌入式系统中,缓存子系统的能耗约占总能耗的一半,动态缓存重构对于降低子系统的能耗是非常有效的。各种研究表明,代码压缩可以显著降低内存需求,并可能在许多情况下提高性能。在本文中,我们研究了将动态缓存重构与代码压缩相结合的挑战和相关机会,以保留这两种方法的优点。实验结果表明,与单独进行动态缓存重构相比,缓存重构和代码压缩的协同组合可以显著降低能耗(平均降低65%)和内存需求,同时显著提高整体性能(高达75%)。
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引用次数: 14
Saving energy in LAN switches: New methods of packet coalescing for Energy Efficient Ethernet 局域网交换机的节能:节能以太网的分组合并新方法
Pub Date : 2011-07-25 DOI: 10.1109/IGCC.2011.6008547
M. Mostowfi, Ken Christensen
Small or home office (SOHO) Ethernet LAN switches consume about 8 TWh per year in the U.S. alone. Despite normally low traffic load and numerous periods of idleness, these switches typically stay fully powered-on at all times. With the standardization of Energy Efficient Ethernet (EEE), Ethernet interfaces can be put into a Low Power Idle (LPI) mode during idle periods when there are no packets to transmit. This paper proposes and evaluates a new EEE policy of synchronous coalescing of packets in network hosts and edge routers. This policy provides extended idle periods for all ports of a LAN switch and thus enables energy savings deeper than in the Ethernet PHY only. We evaluate our method using an ns-2 simulation model of a LAN switch. We show that our method can reduce the overall energy use of a LAN switch by about 40%, while introducing limited and controlled effects on typical Internet traffic and TCP.
仅在美国,小型或家庭办公室(SOHO)以太网LAN交换机每年就消耗约8太瓦时。尽管流量负载通常很低,并且有很多空闲时间,但这些交换机通常始终保持完全通电状态。随着EEE (Energy Efficient Ethernet)标准的标准化,以太网接口可以在无报文传输的空闲时段进入LPI (Low Power Idle)模式。本文提出并评价了一种新的EEE策略,即在网络主机和边缘路由器中同步合并数据包。此策略为LAN交换机的所有端口提供了延长的空闲时间,从而比仅在以太网PHY中节省更多的能源。我们使用局域网交换机的ns-2仿真模型来评估我们的方法。我们表明,我们的方法可以将LAN交换机的总能耗降低约40%,同时对典型的互联网流量和TCP引入有限和可控的影响。
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引用次数: 42
Energy-aware video storage and retrieval in server environments 服务器环境中的能量感知视频存储和检索
Pub Date : 2011-07-25 DOI: 10.1109/IGCC.2011.6008589
Domenic Forte, Ankur Srivastava
As the popularity of video streaming and sharing over the Internet grows, energy consumption in video server environments increases as well. This paper discusses how energy consumption is a critical concern for video servers and can limit their throughput. We investigate the energy consumption of storage components (disks) in video servers and propose two ways to reduce it for better throughput. First, we organize data on disks in a way that allows easier access by exploiting the inherent properties of video access patterns and giving priority to more important video data. Second, the prioritized ordering of video data allows the server to retrieve only the data required to meet quality of service agreements in an energy efficient way. Therefore, the video quality delivered to clients may be scaled in order to service more concurrent requests and/or reduce energy consumption. Results show that our strategies can increase the number of clients served by as much as 114% when compared to conventional approaches while also meeting constraints on video quality and energy consumption.
随着互联网上视频流和共享的普及,视频服务器环境中的能耗也在增加。本文讨论了能源消耗如何成为视频服务器的一个关键问题,并可能限制它们的吞吐量。我们研究了视频服务器中存储组件(磁盘)的能耗,并提出了两种降低能耗的方法,以获得更好的吞吐量。首先,我们利用视频访问模式的固有属性,以一种更容易访问的方式组织磁盘上的数据,并优先考虑更重要的视频数据。其次,视频数据的优先排序允许服务器以节能的方式检索满足服务质量协议所需的数据。因此,交付给客户端的视频质量可以进行缩放,以服务更多的并发请求和/或降低能耗。结果表明,与传统方法相比,我们的策略可以将服务的客户数量增加多达114%,同时满足视频质量和能耗的限制。
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引用次数: 6
Cooling mechanisms in 3D ICs: Thermo-mechanical perspective 三维集成电路中的冷却机制:热机械的观点
Pub Date : 2011-07-25 DOI: 10.1109/IGCC.2011.6008573
S. Kandlikar, D. Kudithipudi, C. Rubio-Jimenez
Three-dimensional (3D) integrated circuits (IC) impose several challenges in thermal management. Stacking vertical layers significantly increases the heat dissipation per unit volume and the thermal footprint per unit area. The internal layers in the stacks are susceptible to high thermal gradients due to the low thermal conductivity interfaces and the distance from the heat sink. Several factors affect the thermal behavior of the 3D IC, including the through silicon vias, bonding, and cooling mechanisms. In this paper, we provide a detailed review of existing cooling mechanisms and their applicability to 3D ICs. We also propose two parameters to account for the thermal interactions among the devices and stack layers for incorporation in the 3D IC cooling system design: Thermal Intensification Factor (TIF) accounts for the increased heat flux due to multiple ICs along the heat transfer path, and Thermal Derating Factor (TDF) accounts for the increased thermal resistance introduced by the multiple layers. Also, a new flow passage design with variable fin density is presented to reduce the surface temperature non-uniformity along the coolant flow length.
三维(3D)集成电路(IC)在热管理方面提出了一些挑战。垂直层的堆叠显著增加了单位体积的散热和单位面积的热足迹。由于低导热界面和与散热器的距离,堆中的内层容易受到高热梯度的影响。影响3D集成电路热性能的因素有几个,包括硅通孔、键合和冷却机制。在本文中,我们提供了现有的冷却机制及其在3D集成电路中的适用性的详细综述。我们还提出了两个参数来解释器件和堆叠层之间的热相互作用,以纳入3D IC冷却系统设计中:热强化因子(TIF)解释了由于沿传热路径的多个IC而增加的热通量,热降额因子(TDF)解释了多层引入的热阻增加。同时,提出了一种新的变翅片密度流道设计,以减小冷却剂流长的表面温度不均匀性。
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引用次数: 9
Analysis and optimization of power consumption in the iterative solution of sparse linear systems on multi-core and many-core platforms 多核与多核平台上稀疏线性系统迭代解的功耗分析与优化
Pub Date : 2011-07-01 DOI: 10.1109/IGCC.2011.6008594
H. Anzt, V. Heuveline, J. Aliaga, María Isabel Castillo, J. C. Fernández, R. Mayo, E. S. Quintana‐Ortí
Energy efficiency is a major concern in modern high-performance-computing. Still, few studies provide a deep insight into the power consumption of scientific applications. Especially for algorithms running on hybrid platforms equipped with hardware accelerators, like graphics processors, a detailed energy analysis is essential to identify the most costly parts, and to evaluate possible improvement strategies. In this paper we analyze the computational and power performance of iterative linear solvers applied to sparse systems arising in several scientific applications. We also study the gains yield by dynamic voltage/frequency scaling (DVFS), and illustrate that this technique alone cannot to reduce the energy cost to a considerable amount for iterative linear solvers. We then apply techniques that set the (multi-core processor in the) host system to a low-consuming state for the time that the GPU is executing. Our experiments conclusively reveal how the combination of these two techniques deliver a notable reduction of energy consumption without a noticeable impact on computational performance.
能源效率是现代高性能计算的主要关注点。然而,很少有研究能深入了解科学应用的功耗。特别是对于在配备硬件加速器(如图形处理器)的混合平台上运行的算法,详细的能量分析对于确定最昂贵的部分并评估可能的改进策略至关重要。本文分析了几种科学应用中应用于稀疏系统的迭代线性求解器的计算性能和功率性能。我们还研究了动态电压/频率缩放(DVFS)产生的增益,并说明这种技术本身不能将迭代线性求解器的能量成本降低到相当大的数量。然后,我们应用技术,将主机系统(多核处理器)设置为GPU执行时的低消耗状态。我们的实验最终揭示了这两种技术的结合如何在不显著影响计算性能的情况下显著降低能耗。
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引用次数: 20
期刊
2011 International Green Computing Conference and Workshops
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