Hasso-Plattner-Institut
Prof. Dr. h.c. mult. Hasso Plattner
 

Stefan Halfpap

Name at Birth: Stefan Klauck

Research Assistant, PhD Student

Phone:+49 (331) 5509-1302
Email:stefan.halfpap(at)hpi.de
Address:August-Bebel-Str. 88, 14482 Potsdam
Room:V-2.02
Links:personal website, dblp, Google Scholar, github, LinkedIn

 

Focus Area: Autonomous Database Management

Research

Efficient Scale-Out Using Query-Driven Workload Distribution and Fragment Allocation

Database replication is an approach for scaling throughput and ensuring high availability. Using workload knowledge, we are able to load-balance queries to replica nodes according to the data being accessed. However, balancing the load evenly while maximizing data reuse is a challenging allocation problem. To address large-size problems, we developed a novel decomposition-based heuristic using linear programming (LP). By using LP, we are flexible to extend our approach for versatile allocation problems, e.g., considering changing workloads and robustness against node failures.

 

Member of Horizon 2020 project

Supervised Master's Theses

  • Towards Heuristic Integer Linear Programming-Based Index Selection Considering Multi-Attribute Indexes and Multi-Index Configurations

  • Cost-efficiency and Performance Robustness in Serverless Join Processing
  • Evaluation of Index Selection Algorithms
  • Network Request Handling in Database Systems
  • Logging and Recovery on In-Memory Databases
  • Partial Database Replication: Comparing Allocation Algorithms for Read-Only Scale-Out

 

Publications

Stefan Halfpap and Rainer Schlosser.
Fragment allocations for partially replicated databases considering data modifications and changing workloads.
Under review, 12 pages.


Stefan Halfpap.
Hybrid index selection using integer linear programming based on cached cost estimates of heuristic approaches.
In Proceedings of the Workshop on Simplicity in Management of Data (SiMoD), 2023.

[doi]    [url]


Peter Boncz, Yannis Chronis, Jan Finis, Stefan Halfpap, Viktor Leis, Thomas Neumann, Anisoara Nica, Caetano Sauer, Knut Stolze, Marcin Zukowski.
SPA: Economical and workload-driven indexing for data analytics in the cloud.
In Proceedings of the International Conference on Data Engineering (ICDE), 2023.

[doi]    [url]


Stefan Halfpap and Rainer Schlosser.
Memory-efficient database fragment allocation for robust load balancing when nodes fail.
In Proceedings of the International Conference on Data Engineering (ICDE), pages 1811–1816, 2021.

[doi]    [download]


Rainer Schlosser and Stefan Halfpap.
Robust and memory-efficient database fragment allocation for large and uncertain database workloads.
In Proceedings of the International Conference on Extending Database Technology (EDBT), pages 367–372, 2021.

[doi]    [url]


Jan Kossmann, Stefan Halfpap, Marcel Jankrift, and Rainer Schlosser.
Magic mirror in my hand, which is the best in the land? An experimental evaluation of index selection algorithms.
Proceedings of the VLDB Endowment, 13(11):2382–2395, 2020.

[doi]    [url]    [download]


Stefan Halfpap and Rainer Schlosser.
Exploration of dynamic query-based load balancing for partially replicated database systems with node failures.
In Proceedings of the International Conference on Information and Knowledge Management (CIKM), pages 3409–3412, 2020.

[doi]    [url]


Rainer Schlosser and Stefan Halfpap.
A decomposition approach for risk-averse index selection.
In Proceedings of the International Conference on Scientific and Statistical Database Management (SSDBM), pages 16:1–16:4, 2020.

[doi]    [download]


Stefan Halfpap.
Efficient scale-out using query-driven workload distribution and fragment allocation.
In Proceedings of the VLDB PhD Workshop, 2019.

[url]


Stefan Halfpap and Rainer Schlosser.
Workload-driven fragment allocation for partially replicated databases using linear programming.
In Proceedings of the International Conference on Data Engineering (ICDE), pages 1746–1749, 2019.

[doi]    [download]


Stefan Halfpap and Rainer Schlosser.
A comparison of allocation algorithms for partially replicated databases.
In Proceedings of the International Conference on Data Engineering (ICDE), pages 2008–2011, 2019.

[doi]    [download]


Markus Dreseler, Jan Kossmann, Martin Boissier, Stefan Klauck, Matthias Uflacker, and Hasso Plattner.
Hyrise re-engineered: An extensible database system for research in relational in-memory data management.
In Proceedings of the International Conference on Extending Database Technology (EDBT), pages 313–324, 2019.

[doi]    [url]


Stefan Klauck, Max Plauth, Sven Knebel, Marius Strobl, Douglas Santry, and Lars Eggert.
Eliminating the bandwidth bottleneck of central query dispatching through TCP connection hand-over.
In Proceedings of the Conference Datenbanksysteme für Business, Technologie und Web (BTW), pages 97–106, 2019.

[doi]    [url]


Jens Hiller, Maël Kimmerlin, Max Plauth, Seppo Heikkilä, Stefan Klauck, Ville Lindfors, Felix Eberhardt, Dariusz Bursztynowski, Jesus Llorente Santos, Oliver Hohlfeld, and Klaus Wehrle.
Giving customers control over their data: Integrating a policy language into the cloud.
In Proceedings of the International Conference on Cloud Engineering (IC2E), pages 241–249, 2018.

[doi]    [download]


David Schwalb, Jan Kossmann, Martin Faust, Stefan Klauck, Matthias Uflacker, and Hasso Plattner.
Hyrise-R: Scale-out and hot-standby through lazy master replication for enterprise applications.
In Proceedings of the International Workshop on In-Memory Data Management and Analytics (IMDM), pages 7:1–7:7, 2015.

[doi]    [url]


Stefan Klauck, Lars Butzmann, Stephan Müller, Martin Faust, David Schwalb, Matthias Uflacker, Werner Sinzig, and Hasso Plattner.
Interactive, flexible, and generic what-if analyses using in-memory column stores.
In Proceedings of the International Conference on Database Systems for Advanced Applications (DASFAA), pages 488–497, 2015.

[doi]    [download]


Stephan Müller, Anisoara Nica, Lars Butzmann, Stefan Klauck, and Hasso Plattner.
Using object-awareness to optimize join processing in the SAP HANA aggregate cache.
In Proceedings of the International Conference on Extending Database Technology (EDBT), pages 557–568, 2015.

[doi]    [url]


Lars Butzmann, Stefan Klauck, Stephan Müller, Matthias Uflacker, Werner Sinzig, and Hasso Plattner.
Generic business simulation using an in-memory column store.
In Proceedings of the Conference Datenbanksysteme für Business, Technologie und Web (BTW), pages 633–643, 2015.

[gi handle]    [url]


Stephan Müller, Lars Butzmann, Stefan Klauck, and Hasso Plattner.
An adaptive aggregate maintenance approach for mixed workloads in columnar in-memory databases.
In Proceedings of the Australasian Computer Science Conference (ACSC), pages 3–12, 2014.

[url]


Stephan Müller, Lars Butzmann, Stefan Klauck, and Hasso Plattner.
Workload-aware aggregate maintenance in columnar in-memory databases.
In Proceedings of the International Conference on Big Data (BigData), pages 62–69, 2013.

[doi]


Stephan Müller, Lars Butzmann, Kai Höwelmeyer, Stefan Klauck, and Hasso Plattner.
Efficient view maintenance for enterprise applications in columnar in-memory databases.
In Proceedings of the International Enterprise Distributed Object Computing Conference (EDOC), pages 249–258, 2013.

[doi]


Christian Tinnefeld, Stephan Müller, Helen Kaltegärtner, Sebastian Hillig, Lars Butzmann, David Eickhoff, Stefan Klauck, Daniel Taschik, Björn Wagner, Oliver Xylander, Alexander Zeier, Hasso Plattner, and Cafer Tosun.
Available-to-promise on an in-memory column store.
In Proceedings of the Conference Datenbanksysteme für Business, Technologie und Web (BTW), pages 667–686, 2011.

[gi handle]    [url]