454 research outputs found
Medium access control in wireless network-on-chip: a context analysis
© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Wireless on-chip communication is a promising candidate to address the performance and efficiency issues that arise when scaling current NoC techniques to manycore processors. A WNoC can serve global and broadcast traffic with ultra-low latency even in thousand-core chips, thus acting as a natural complement to conventional and throughput-oriented wireline NoCs. However, the development of MAC strategies needed to efficiently share the wireless medium among the increasing number of cores remains a considerable challenge given the singularities of the environment and the novelty of the research area. In this position article, we present a context analysis describing the physical constraints, performance objectives, and traffic characteristics of the on-chip communication paradigm. We summarize the main differences with respect to traditional wireless scenarios, and then discuss their implications on the design of MAC protocols for manycore WNoC, with the ultimate goal of kickstarting this arguably unexplored research area.Peer ReviewedPostprint (author's final draft
Best practices for HPM-assisted performance engineering on modern multicore processors
Many tools and libraries employ hardware performance monitoring (HPM) on
modern processors, and using this data for performance assessment and as a
starting point for code optimizations is very popular. However, such data is
only useful if it is interpreted with care, and if the right metrics are chosen
for the right purpose. We demonstrate the sensible use of hardware performance
counters in the context of a structured performance engineering approach for
applications in computational science. Typical performance patterns and their
respective metric signatures are defined, and some of them are illustrated
using case studies. Although these generic concepts do not depend on specific
tools or environments, we restrict ourselves to modern x86-based multicore
processors and use the likwid-perfctr tool under the Linux OS.Comment: 10 pages, 2 figure
The MANGO FET-HPC Project: an overview
© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper, we provide an overview of the MANGO project
and its goal. The MANGO project aims at addressing power, performance
and predictability (the PPP space) in future High-Performance Computing
systems. It starts from the fundamental intuition that effective
techniques for all three goals ultimately rely on customization to adapt
the computing resources to reach the desired Quality of Service (QoS).
From this starting point, MANGO will explore different but interrelated
mechanisms at various architectural levels, as well as at the level of
the system software. In particular, to explore a new positioning across
the PPP space, MANGO will investigate system-wide, holistic, proactive
thermal and power management aimed at extreme-scale energy efficiency.The MANGO project starts in October 2015 and is funded by the European Commission under the Horizon 2020 FET-HPC program. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 671668.Flich Cardo, J.; Agosta, G.; Ampletzer, P.; Atienza Alonso, D.; Cilardo, A.; Fornaciari, W.; Kovac, M.... (2015). The MANGO FET-HPC Project: an overview. IEEE Computer Society. https://doi.org/10.1109/CSE.2015.57
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