1,721,173 research outputs found
AXIOM: a scalable, efficient and reconfigurable embedded platform
No full textCyber-Physical Systems (CPSs) are becoming widely used in every application that requires interaction between humans and the physical environment. People expect this interaction to happen in real-time and this creates pressure onto system designs due to the ever-higher demand for data processing in the shortest possible and predictable time. Additionally, easy programmability, energy efficiency, and modular scalability are also important to ensure these systems to become widespread. All these requirements push new scientific and technological challenges towards the engineering community. The AXIOM project (Agile, eXtensible, fast I/O Module), presented in this paper, introduces a new hardware-software platform for CPS, which can provide an easy parallel programming model and fast connectivity, in order to scale-up performance by adding multiple boards. The AXIOM platform consists of a custom board based on a Xilinx Zynq Ultrascale+ ZU9EG SoC including
four 64-bit ARM cores, the Arduino socket and four high-speed (up to 18 Gbps) connectors on USB-C receptacles. By relying on this hardware, DF-Threads, a novel execution model based on
dataflow modality, has been developed and tested. In this paper, we highlight some major conclusions of the AXIOM project, such as the gain in performance compared to other parallel programming models such as OpenMPI and Cilk
Analyzing the Impact of Operating System Activity of different Linux Distributions in a Distributed Environment
No full textA rise in the number of threads in large-scale applications running on multi-node architectures makes operating system activity increasingly more relevant. Therefore, evaluation methodologies need to account for these activities. We decided to build our evaluation environment through the COTSon simulator. Moreover, our environment permits flexible Design Space Exploration (DSE) by making easy the management of many experiments and the characterizations of Operating System (OS) activity. In this paper, we show the result analysis tool flow and the OS impact of different Linux distributions running on a distributed environment consisting of several nodes with a full OS. In order to quantify our results, we use matrix multiplication benchmark executed through a DataFlow model, named DataFlow Threads(DF-Threads). We analyze key metrics like L2 cache miss rate, execution cycles, data access latency, and kernel cycles showing up to 60% performance variations among the different OS distributions
Bridging a Data-Flow Execution Model to a Lightweight Programming Model
No full textStarting from a Data-Flow execution model called “DF-Threads”, we defined a minimalistic API to enable an efficient implementation in the hardware of the distribution of the threads across the cores of a single multi-core system and across the remote cores of a cluster. We aim at proposing this API as a simple programming model in C language that can potentially permit an easy interface between DF-Threads and generic programming models. Clusters are typically programmed with MPI, therefore we evaluated our approach against OpenMPI. If we consider the delivered GFLOPS per core, DF-Threads are also competitive in respect to CUDA. In the basic examples, that we used in this initial investigation, DF-Threads achieve better performance-per-core compared to OpenMPI and CUDA.
In particular, OpenMPI has a large portion of OS-kernel activity, which is slowing down its performance
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Diagnosi radiologica delle alterazioni degenerative dell'articolazione temporo-mandibolare
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