EDBT 2026 Demo / reviewers in the wild / expert
Joel Witzke
dblp:329/5086
· DBLP profile ↗
5ranked-venue papers in the field
1as first author
5since 2021 · last 2025
0000-0002-0831-8078ORCID · corroborated
Domains — venue-derived; a paper can count in several
Big Data, Cloud & Distributed Data Systems · 5 (1 first)
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2025 | Optimizing Memory Allocation in Distributed Clusters with Predictive ModelingabstractIn modern distributed systems, efficient resource allocation is a vital aspect to maintain scalability, reduce operational costs, and ensure fast execution even across heterogeneous workloads. Predictive models for resource usage are essential tools for optimizing allocation and preventing system bottlenecks. Predictive memory allocation has asymmetric costs as a key challenge: underallocation causes failures while overallocation wastes memory. We propose a regression method based on a LightGBM and XGBoost ensemble trained to predict high conditional quantiles. To further account for the high cost of underallocations we add a multiplicative safety factor. With our method we are able to reduce the number of under-allocated jobs from 4.17% to 2.89% and average overallocation from 148% to 44.51% on a real-world dataset of build jobs provided by SAP. We further explore the pareto frontier between optimization for underallocation and for overallocation. Jonathan Bader, Edgar Blumenthal, Marten Eckardt, Justus Krebs, Joel Witzke, Xemena Wysokinska, Haci Ismail Aslan, Odej Kao |
IEEE Big Data | 5 |
| 2025 | Learning Process Energy Profiles from Node-Level Power Data
Jonathan Bader, Julius Irion, Jannis Kappel, Joel Witzke, Niklas Fomin, Diellza Sherifi, Odej Kao |
IEEE Big Data | 4 |
| 2023 | Proactive Resource Management to Optimize Distributed Workflow ExecutionsabstractScientific workflows have received increasing interest and are used in many scientific fields to gather, analyze, and process significant amounts of data. However, their tasks are usually treated as black boxes, and their behavior remains unconsidered for resource allocations, which can lead to subpar resource allocations with typical scheduling. Although not done yet, it should be possible to observe such tasks, learn their behavior, and use this knowledge to improve future executions. As workflows and their tasks are often executed multiple times on a massive scale, even a slight improvement per execution may save hours of execution time and significant amounts of energy.To achieve this goal, we develop an innovative approach to model task executions and predict resource usage. The prediction is embedded in a feedback loop to repeatedly improve the models and to closely track workflow executions to make predictions and resource allocations accurate. Joel Witzke, Florian Schintke, Ansgar Lößer, Björn Scheuermann 0001 |
IEEE Big Data | 1 |
| 2022 | Towards Advanced Monitoring for Scientific WorkflowsabstractScientific workflows consist of thousands of highly parallelized tasks executed in a distributed environment involving many components. Automatic tracing and investigation of the components’ and tasks’ performance metrics, traces, and behavior are necessary to support the end user with a level of abstraction since the large amount of data cannot be analyzed manually. The execution and monitoring of scientific workflows involves many components, the cluster infrastructure, its resource manager, the workflow, and the workflow tasks. All components in such an execution environment access different monitoring metrics and provide metrics on different abstraction levels. The combination and analysis of observed metrics from different components and their interdependencies are still widely unregarded.We specify four different monitoring layers that can serve as an architectural blueprint for the monitoring responsibilities and the interactions of components in the scientific workflow execution context. We describe the different monitoring metrics subject to the four layers and how the layers interact. Finally, we examine five state-of-the-art scientific workflow management systems (SWMS) in order to assess which steps are needed to enable our four-layer-based approach. Jonathan Bader, Joel Witzke, Sören Becker 0001, Ansgar Lößer, Fabian Lehmann, Leon Doehler, Duc Anh Vu 0001, Odej Kao |
IEEE Big Data | 2 |
| 2022 | BottleMod: Modeling Data Flows and Tasks for Fast Bottleneck AnalysisabstractIn the recent years, scientific workflows gained more and more popularity. In scientific workflows, tasks are typically treated as black boxes. Dealing with their complex interrelations to identify optimization potentials and bottlenecks is therefore inherently hard. The progress of a scientific workflow depends on several factors, including the available input data, the available computational power, and the I/O and network bandwidth. Here, we tackle the problem of predicting the workflow progress with very low overhead. To this end, we look at suitable formalizations for the key parameters and their interactions which are sufficiently flexible to de scribe the input da ta consumption, the computational effort and the output production of the workflow’s tasks. At the same time they allow for computationally simple and fast performance predictions, including a bottleneck analysis over the workflow runtime. A piecewise-defined bottleneck function is derived from the discrete intersections of the task models’ limiting functions. This allows to estimate potential performance gains from overcoming the bottlenecks and can be used as a basis for optimized resource allocation and workflow execution. Ansgar Lößer, Joel Witzke, Florian Schintke, Björn Scheuermann 0001 |
IEEE Big Data | 2 |