LEGaTO: first steps towards energy-efficient toolset for heterogeneous computing

LEGaTO is a three-year EU H2020 project which started in December 2017. The LEGaTO project will leverage task-based programming models to provide a software ecosystem for Made-in-Europe heterogeneous hardware composed of CPUs, GPUs, FPGAs and dataflow engines. The aim is to attain one order of magnitude energy savings from the edge to the converged cloud/HPC.Peer ReviewedPostprint (author's final draft

Environmental-Based Characterization of SoC-Based Instrumentation Systems for Stratified Testing

This paper proposes a novel environmental-based method for evaluating the good yield rate (GYR) of systems-on-chip (SoC) during fabrication. Testing and yield evaluation at high confidence are two of the most critical issues for the success of SoC as a viable technology. The proposed method relies on different features of fabrication, which are quantified by the so-called Fabrication environmental parameters (EPs). EPs can be highly correlated to the yield, so they are analyzed using statistical methods to improve its accuracy and ultimately direct the test process to an efficient execution. The novel contributions of the proposed method are: 1) to establish an adequate theoretical foundation for understanding the fabrication process of SoCs together with an assurance of the yield at a high confidence level and 2) to ultimately provide a realistic approach to SoC testing with an accurate yield evaluation. Simulations are provided to demonstrate that the proposed method significantly improves the confidence interval of the estimated yield as compared with existing testing methodologies such as random testing (RT)

On Leveraging Partial Paths in Partially-Connected Networks

Mobile wireless network research focuses on scenarios at the extremes of the network connectivity continuum where the probability of all nodes being connected is either close to unity, assuming connected paths between all nodes (mobile ad hoc networks), or it is close to zero, assuming no multi-hop paths exist at all (delay-tolerant networks). In this paper, we argue that a sizable fraction of networks lies between these extremes and is characterized by the existence of partial paths, i.e. multi-hop path segments that allow forwarding data closer to the destination even when no end-to-end path is available. A fundamental issue in such networks is dealing with disruptions of end-to-end paths. Under a stochastic model, we compare the performance of the established end-to-end retransmission (ignoring partial paths), against a forwarding mechanism that leverages partial paths to forward data closer to the destination even during disruption periods. Perhaps surprisingly, the alternative mechanism is not necessarily superior. However, under a stochastic monotonicity condition between current v.s. future path length, which we demonstrate to hold in typical network models, we manage to prove superiority of the alternative mechanism in stochastic dominance terms. We believe that this study could serve as a foundation to design more efficient data transfer protocols for partially-connected networks, which could potentially help reducing the gap between applications that can be supported over disconnected networks and those requiring full connectivity.Comment: Extended version of paper appearing at IEEE INFOCOM 2009, April 20-25, Rio de Janeiro, Brazi

Symbiosis between the TRECVid benchmark and video libraries at the Netherlands Institute for Sound and Vision

Audiovisual archives are investing in large-scale digitisation efforts of their analogue holdings and, in parallel, ingesting an ever-increasing amount of born- digital files in their digital storage facilities. Digitisation opens up new access paradigms and boosted re-use of audiovisual content. Query-log analyses show the shortcomings of manual annotation, therefore archives are complementing these annotations by developing novel search engines that automatically extract information from both audio and the visual tracks. Over the past few years, the TRECVid benchmark has developed a novel relationship with the Netherlands Institute of Sound and Vision (NISV) which goes beyond the NISV just providing data and use cases to TRECVid. Prototype and demonstrator systems developed as part of TRECVid are set to become a key driver in improving the quality of search engines at the NISV and will ultimately help other audiovisual archives to offer more efficient and more fine-grained access to their collections. This paper reports the experiences of NISV in leveraging the activities of the TRECVid benchmark

Lessons from an Open Source Business

Creating a successful company is difficult; but creating a successful company, a successful open source project, and a successful ecosystem all at the same time is much more difficult. This article takes a retrospective look at some of the lessons we have learned in building BigBlueButton, an open source web conferencing system for distance education, and in building Blindside Networks, a company following the traditional business model of providing support and services to paying customers. Our main message is that the focus must be on creating a successful open source project first, for without it, no company in the ecosystem can flourish