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2. Work-in-Progress: Evaluating Task Dropping Strategies for Overloaded Real-Time Systems

Author

Gao, Yiqin, Pallez, Guillaume, Robert, Yves, Vivien, Frédéric, École normale supérieure de Lyon (ENS de Lyon), Optimisation des ressources : modèles, algorithmes et ordonnancement (ROMA), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de l'Informatique du Parallélisme (LIP), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Topology-Aware System-Scale Data Management for High-Performance Computing (TADAAM), Laboratoire Bordelais de Recherche en Informatique (LaBRI), Université de Bordeaux (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), The work of Yiqin Gao was supported by the LABEX MILYON (ANR-10-LABX-0070) of Université de Lyon, within the program 'Investissements d’Avenir' (ANR-11-IDEX-0007) operated by the French National Research Agency (ANR)., École normale supérieure - Lyon (ENS Lyon), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Inria Bordeaux - Sud-Ouest

Subjects
[INFO.INFO-PF]Computer Science [cs]/Performance [cs.PF], real-time system, [INFO]Computer Science [cs], overloaded system, task dropping
Abstract

International audience; This paper discusses evaluation criteria and scheduling strategies for the analysis of overloaded real-time systems. This work builds upon techniques from queueing theory and proposes a new approach for real-time systems.

Published
2021

3. Texture Analysis Of T1-Weighted Turbo Spin-Echo Mri For The Diagnosis And Follow-Up Of Collagen Vi-Related Myopathy

Author

David Gómez-Andrés, Rafael C. Rodrigues, Antonio M. G. Pinheiro, Robert-Yves Carlier, Susana Quijano-Roy, Mickael Tordjman, and Marta Gomez Garcia de la Banda

Subjects
medicine.diagnostic_test, Ullrich congenital muscular dystrophy, Feature extraction, Bethlem myopathy, Magnetic resonance imaging, 02 engineering and technology, medicine.disease, 03 medical and health sciences, 0302 clinical medicine, Nuclear magnetic resonance, Feature (computer vision), Computer-aided diagnosis, Collagen VI, 0202 electrical engineering, electronic engineering, information engineering, medicine, 020201 artificial intelligence & image processing, medicine.symptom, Myopathy, 030217 neurology & neurosurgery, Mathematics
Abstract

Muscle texture analysis in Magnetic Resonance Imaging (MRI) has revealed a good correlation with typical histological changes resulting from neuromuscular disorders. In this research, we assess the effectiveness of several features in describing intramuscular texture alterations in cases of Collagen VI-related myopathy. A T1-weighted Turbo Spin-Echo MRI dataset was used $(\mathrm{N}_{subj}\,=26)$, consisting of thigh scans from subjects diagnosed with Ullrich Congenital Muscular Dystrophy or Bethlem Myopathy, with different severity levels, as well as healthy subjects. A total of 355 texture features were studied, including attributes derived from the Gray-Level Co-occurrence Matrix, the Run-Length Matrix, Wavelet and Gabor filters. The extracted features were ranked using the Support Vector Machine Recursive Feature Elimination (SVM-RFE) algorithm with Correlation Bias Reduction, prior to cross-validated classification with a Gaussian kernel SVM.

Published
2021

7. Resilient Scheduling of Moldable Parallel Jobs to Cope With Silent Errors.

Author

Benoit, Anne, Le Fevre, Valentin, Perotin, Lucas, Raghavan, Padma, Robert, Yves, and Sun, Hongyang

Abstract

We study the resilient scheduling of moldable parallel jobs on high-performance computing (HPC) platforms. Moldable jobs allow for choosing a processor allocation before execution, and their execution time obeys various speedup models. The objective is to minimize the overall completion time or the makespan, when jobs can fail due to silent errors and hence may need to be re-executed after each failure until successful completion. Our work generalizes the classical scheduling framework for failure-free jobs. To cope with silent errors, we introduce two resilient scheduling algorithms, Lpa-List and Batch-List, both of which use the List strategy to schedule the jobs. Without knowing a priori how many times each job will fail, Lpa-List relies on a local strategy to allocate processors to the jobs, while Batch-List schedules the jobs in batches and allows only a restricted number of failures per job in each batch. We prove approximation ratios for the two algorithms under several prominent speedup models (e.g., roofline, communication, Amdahl, power, monotonic, and a mix model). An extensive set of simulations is conducted to evaluate different variants of the two algorithms, and the results show that they consistently outperform some baseline heuristics. Overall, our best algorithm is within a factor of 1.6 of a lower bound on average over the entire set of experiments, and within a factor of 4.2 in the worst case. [ABSTRACT FROM AUTHOR]

Published
2022
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35. Checkpointing Workflows for Fail-Stop Errors.

Author

Han, Li, Canon, Louis-Claude, Casanova, Henri, Robert, Yves, and Vivien, Frederic

Subjects
WORKFLOW management systems, DIRECTED acyclic graphs, PARALLEL programs (Computer programs), COMPUTING platforms, COMPUTER algorithms
Abstract

We consider the problem of orchestrating the execution of workflow applications structured as Directed Acyclic Graphs (DAGs) on parallel computing platforms that are subject to fail-stop failures. The objective is to minimize expected overall execution time, or makespan. A solution to this problem consists of a schedule of the workflow tasks on the available processors and of a decision of which application data to checkpoint to stable storage, so as to mitigate the impact of processor failures. To address this challenge, we consider a restricted class of graphs, Minimal Series-Parallel Graphs (M-SPGs), which is relevant to many real-world workflow applications. For this class of graphs, we propose a recursive list-scheduling algorithm that exploits the M-SPG structure to assign sub-graphs to individual processors, and uses dynamic programming to decide how to checkpoint these sub-graphs. We assess the performance of our algorithm for production workflow configurations, comparing it to an approach in which all application data is checkpointed and an approach in which no application data is checkpointed. Results demonstrate that our algorithm outperforms both the former approach, because of lower checkpointing overhead, and the latter approach, because of better resilience to failures. [ABSTRACT FROM AUTHOR]

Published
2018
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40. Towards Optimal Multi-Level Checkpointing.

Author

Benoit, Anne, Cavelan, Aurelien, Le Fevre, Valentin, Robert, Yves, and Sun, Hongyang

Subjects
FAULT-tolerant computing, DYNAMIC programming, COMPUTER algorithms, HEURISTIC algorithms, COMPUTER network protocols
Abstract

We provide a framework to analyze multi-level checkpointing protocols, by formally defining a k -level checkpointing pattern. We provide a first-order approximation to the optimal checkpointing period, and show that the corresponding overhead is in the order of \sum _{\ell =1}^{k}\sqrt{2\lambda _\ell C_\ell} , where \lambda _\ell$ is the error rate at level  $\ell$ , and $C_\ell$ the checkpointing cost at level $\ell$ . This nicely extends the classical Young/Daly formula on single-level checkpointing. Furthermore, we are able to fully characterize the shape of the optimal pattern (number and positions of checkpoints), and we provide a dynamic programming algorithm to determine the optimal subset of levels to be used. Finally, we perform simulations to check the accuracy of the theoretical study and to confirm the optimality of the subset of levels returned by the dynamic programming algorithm. The results nicely corroborate the theoretical study, and demonstrate the usefulness of multi-level checkpointing with the optimal subset of levels. [ABSTRACT FROM AUTHOR]

Published
2017
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41. Toward an Optimal Online Checkpoint Solution under a Two-Level HPC Checkpoint Model.

Author

Di, Sheng, Robert, Yves, Vivien, Frederic, and Cappello, Franck

Subjects
*HIGH performance computing, *FAULT tolerance (Engineering), *COMPUTER network protocols, *MATHEMATICAL optimization, *MULTILEVEL models
Abstract

The traditional single-level checkpointing method suffers from significant overhead on large-scale platforms. Hence, multilevel checkpointing protocols have been studied extensively in recent years. The multilevel checkpoint approach allows different levels of checkpoints to be set (each with different checkpoint overheads and recovery abilities), in order to further improve the fault tolerance performance of extreme-scale HPC applications. How to optimize the checkpoint intervals for each level, however, is an extremely difficult problem. In this paper, we construct an easy-to-use two-level checkpoint model. Checkpoint level 1 deals with errors with low checkpoint/recovery overheads such as transient memory errors, while checkpoint level 2 deals with hardware crashes such as node failures. Compared with previous optimization work, our new optimal checkpoint solution offers two improvements: (1) it is an online solution without requiring knowledge of the job length in advance, and (2) it shows that periodic patterns are optimal and determines the best pattern. We evaluate the proposed solution and compare it with the most up-to-date related approaches on an extreme-scale simulation testbed constructed based on a real HPC application execution. Simulation results show that our proposed solution outperforms other optimized solutions and can improve the performance significantly in some cases. Specifically, with the new solution the wall-clock time can be reduced by up to 25.3 percent over that of other state-of-the-art approaches. Finally, a brute-force comparison with all possible patterns shows that our solution is always within $1$ percent of the best pattern in the experiments. [ABSTRACT FROM PUBLISHER]

Published
2017
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42. Complexity results and heuristics for pipelined multicast operations on heterogeneous platforms

Author

Beaumont, Olivier, Legrand, Arnaud, Marchal, Loris, Robert, Yves, Laboratoire Bordelais de Recherche en Informatique (LaBRI), Université de Bordeaux (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS), Algorithms and high performance computing for grand challenge applications (SCALAPPLIX), INRIA Futurs, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS), Algorithms and Scheduling for Distributed Heterogeneous Platforms (GRAAL), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de l'Informatique du Parallélisme (LIP), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Informatique du Parallélisme (LIP), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS), Regularity and massive parallel computing (REMAP), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Centre National de la Recherche Scientifique (CNRS)-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-École normale supérieure - Lyon (ENS Lyon), INRIA, LIP, École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL)

Subjects
REGIME PERMANENT, STEADY-STATE, 020203 distributed computing, COMPLEXITY, HETEROGENEOUS PLATFORMS, [INFO.INFO-OH]Computer Science [cs]/Other [cs.OH], 02 engineering and technology, SCHEDULING, ORDONNANCEMENT, COMPLEXITE, Computer Science::Networking and Internet Architecture, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], PLATEFORMES HETEROGENES
Abstract

In this paper, we consider the communications involved by the execution of a complex application deployed on a heterogeneous platform. Such applications extensively use macro-communication schemes, for example to broadcast data items to several targets, known as the multicast operation. Rather than seeking to minimize the execution time of a single multicast, we focus on steady-state performance. We target heterogeneous platforms, modeled by a graph where resources have different communication speeds. We show that the problem of computing the best throughput for a multicast operation is NP-hard, whereas the best throughput to broadcast a message to every node in a graph can be computed in polynomial time. Thus we introduce several heuristics to deal with this problem; most of them are based on linear programming. We prove that some of these heuristics are approximation algorithms. We perform simulations to test these heuristics and show that their results are close to a theoretical upper bound on the throughput that we obtain with the linear programming approach.; Nous nous intéressons ici aux communications qui ont lieu lors de l’exécution d’une application complexe distribuée sur un environnement hétérogène de type “grille de calcul”. De telles applications font un usage intensif des primitives de communications collectives, comme par exemple le multicast (diffusion de données vers plusieurs cibles). Nous supposons qu’il y a un grand nombre de messages `a diffuser et cherchons à optimiser le débit de telles opérations en régime permanent. La plate-forme hétérogène sous-jacente est modélisée par un graphe où les différentes ressources (processeurs, liens de communication) ont des vitesses diff ́e-rentes. Nous montrons que calculer le meilleur débit pour une opération de multicast est un problème NP-dur, alors le meilleur débit pour un broadcast (diffusion vers tous les nœuds de la plate-forme) peut être calculé en temps polynomial. Nous introduisons donc plusieurs heuristiques pour le problème du multicast, dont la plupart sont basées sur la programmation linéaire, et dont certaines sont garanties à un facteur près de l’optimal. Nous réalisons des simulations pour tester les performances de ces heuristiques et montrons que leur résultat est proche d’une borne supérieure théorique sur le débit que nous avons obtenue avec notre approche utilisant la programmation linéaire.

Published
2004

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