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Auflistung nach Autor:in "Klauck, Stefan"

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  • Konferenzbeitrag
    Available-to-promise on an in-memory column store
    (Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Tinnefeld, Christian; Müller, Stephan; Kaltegärtner, Helen; Hillig, Sebastian; Butzmann, Lars; Eickhoff, David; Klauck, Stefan; Taschik, Daniel; Wagner, Björn; Xylander, Oliver; Tosun, Cafer; Zeier, Alexander; Plattner, Hasso
    Available-To-Promise (ATP) is an application in the context of Supply Chain Management (SCM) systems and provides a checking mechanism that calculates if the desired products of a customer order can be delivered on the requested date. Modern SCM systems store relevant data records as aggregated numbers which implies the disadvantages of maintaining redundant data as well as inflexibility in querying the data. Our approach omits aggregates by storing all individual data records in an in-memory, column-store and scans through all relevant records on-the-fly for each check. We contribute by describing the novel data organization and a lockingfree, highly-concurrent ATP checking algorithm. Additionally, we explain how new business functionality such as instant rescheduling of orders can be realized with our approach. All concepts are implemented within a prototype and benchmarked by using an anonymized SCM dataset of a Fortune 500 consumer products company. The paper closes with a discussion of the results and gives an outlook how this approach can help companies to find the right balance between low inventory costs and high order fulfillment rates.
  • Textdokument
    Eliminating the Bandwidth Bottleneck of Central Query Dispatching Through TCP Connection Hand-Over
    (BTW 2019, 2019) Klauck, Stefan; Plauth, Max; Knebel, Sven; Strobl, Marius; Santry, Douglas; Eggert, Lars
    In scale-out database architectures, client queries must be routed to individual backend database servers for processing. In dynamic database systems, where backend servers join and leave a cluster or data partitions move between servers, clients do not know which server to send queries to. Using a central dispatcher, all queries and responses are routed via a single node. In a system with many high-performance backends, such a central node can become the system bottleneck. This paper compares three different approaches for query dispatching in terms of scaling network throughput and processing flexibility. Off-the-shelf TCP/HTTP load-balancers cannot dispatch individual queries arriving over a single connection to different backend servers, unless they are extended to understand the database wire protocol. For small response sizes up to 4 KB, a purpose-built query dispatcher delivers the highest throughput. For larger responses (i.e., BLOBs or data sets for external analysis), a novel approach for network proxying that transparently maps TCP connections between backend servers performs best.We propose hybrid query dispatching that performs a TCP connection hand-over on demand when returning large database results.
  • Konferenzbeitrag
    Generic Business Simulation Using an In-Memory Column Store
    (Datenbanksysteme für Business, Technologie und Web (BTW 2015), 2015) Butzmann, Lars; Klauck, Stefan; Müller, Stephan; Uflacker, Matthias; Sinzig, Werner; Plattner, Hasso
    Value driver trees are a well-known methodology to model dependencies such as the definition of key performance indicators. While the models have well-known semantics, they lack the right tool support for business simulations, because a flexible implementation that supports multidimensional, hierarchical value driver trees and data bindings is very complex and computationally challenging. This paper tackles this problem by proposing an approach for generic enterprise simulations which are based on value driver trees. Our approach is two-fold: we present the definition of a simulation meta model at design time, and the run-time simulation tool. The simulation meta model describes the structure of the dependency graph, the data binding, and the parametrization of the model to simulate data changes. The simulation tool can then be used to create and edit simulation model instances and run simulations in real-time by leveraging an in-memory column store. Besides the formal description of the approach, this work presents a prototypical implementation of the simulation tool and an evaluation using data of a consumer packaged goods company.