Section: New Results

Trace and Statistical Analysis

• In [19], we present visual analysis techniques to evaluate the performance of HPC task-based applications on hybrid architectures. Our approach is based on composing modern data analysis tools (pjdump, R, ggplot2, plotly), enabling an agile and flexible scripting framework with minor development cost. We validate our proposal by analyzing traces from the full-fledged implementation of the Cholesky decomposition available in the MORSE library running on a hybrid (CPU/GPU) platform. The analysis compares two different workloads and three different task schedulers from the StarPU runtime system. Our analysis based on composite views allows to identify allocation mistakes, priority problems in scheduling decisions, GPU tasks anomalies causing bad performance, and critical path issues.

• Media events are an area of major concern for the science of territory, with a combination of empirical, methodological and theoretical fields of research. The paper [22] presents three variations of increasing complexity around the questions of the application of the concepts of “territory”, “territoriality” and “territorialization” to the description of media events. Each variation is illustrated by recent results from the research project ANR Geomedia on a corpus of international RSS flows produced by newspapers of French, English and Spanish language located in various countries of the world.