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Auflistung nach Autor:in "Jacobs, Dean"

1 - 4 von 4
  • Konferenzbeitrag
    Anforderungen an Datenbanksysteme für Multi-Tenancy- und Software-as-a-Service-Applikationen
    (Datenbanksysteme in Business, Technologie und Web (BTW) – 13. Fachtagung des GI-Fachbereichs "Datenbanken und Informationssysteme" (DBIS), 2009) Aulbach, Stefan; Jacobs, Dean; Primsch, Jürgen; Kemper, Alfons
    Für Multi-Tenancy-Applikationen und Software as a Service (SaaS) stellen sich konventionelle Datenbanksysteme oftmals als ungeeignet heraus. In einem solchen Umfeld müssen Anforderungen, wie Erweiterbarkeit und Verfügbarkeit, trotz geringer Kosten für den
  • Konferenzbeitrag
    Ruminations on Multi-Tenant Databases
    (Datenbanksysteme in Business, Technologie und Web (BTW 2007) – 12. Fachtagung des GI-Fachbereichs "Datenbanken und Informationssysteme" (DBIS), 2007) Jacobs, Dean; Aulbach, Stefan
    This is a position paper on multi-tenant databases. As motivation, it first describes the emerging marketplace of hosted enterprise services and the importance of using multi-tenancy to handle high traffic volumes at low cost. It then outlines the main requirements on multi-tenant databases: scale up by consolidating multiple tenants onto the same server and scale out by providing an administrative framework that manages a farm of such servers. Finally it describes three approaches to implementing multi-tenant databases and compares them based on some simple experiments. The main conclusion is that existing database vendors need to enhance their products to better support multi-tenancy.
  • Konferenzbeitrag
    Simulating multi-tenant OLAP database clusters
    (Datenbanksysteme für Business, Technologie und Web (BTW), 2011) Schaffner, Jan; Eckart, Benjamin; Schwarz, Christian; Brunnert, Jan; Jacobs, Dean; Zeier, Alexander; Plattner, Hasso
    Simulation of parallel database machines was used in many database research projects during the 1990ies. One of the main reasons why simulation approaches were popular in that time was the fact that clusters with hundreds of nodes were not as readily available for experimentation as it is the case today. At the same time, the simulation models underlying these systems were fairly complex since they needed to capture both queuing processes in hardware (e.g. CPU contention or disk I/O) and software (e.g. processing distributed joins). Todays trend towards more specialized database architectures removes large parts of this complexity from the modeling task. As the main contribution of this paper, we discuss how we developed a simple simulation model of such a specialized system: a multi-tenant OLAP cluster based on an in-memory column database. The original infrastructure and testbed was built using SAP TREX, an in-memory column database part of SAP's business warehouse accelerator, which we ported to run on the Amazon EC2 cloud. Although we employ a simple queuing model, we achieve good accuracy. Similar to some of the parallel systems of the 1990ies, we are interested in studying different replication and high-availability strategies with the help of simulation. In particular, we study the effects of mirrored vs. interleaved replication on throughput and load distribution in our cluster of multi-tenant databases. We show that the better load distribution inherent to the interleaved replication strategy is exhibited both on EC2 and in our simulation environment.
  • Konferenzbeitrag
    Software as a service: Do it yourself or use the cloud
    (Datenbanksysteme in Business, Technologie und Web (BTW) – 13. Fachtagung des GI-Fachbereichs "Datenbanken und Informationssysteme" (DBIS), 2009) Jacobs, Dean
    In the Software as a Service (SaaS) model, a service provider owns and operates an application that is accessed by many businesses over the Internet. A key benefit of this model is that, by careful engineering, it is possible to leverage economy of scale