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Diversified Stress Testing of RDF Data Management Systems
TLDR
This work performs an in-depth experimental analysis that shows existing SPARQL benchmarks are not suitable for testing systems for diverse queries and varied workloads and provides stress testing tools for RDF data management systems, and uses the Waterloo SParQL Diversity Test Suite (WatDiv) to address these shortcomings.
HDRF: Stream-Based Partitioning for Power-Law Graphs
TLDR
This paper proposes High-Degree (are) Replicated First (HDRF), a novel streaming vertex-cut graph partitioning algorithm that effectively exploits skewed degree distributions by explicitly taking into account vertex degree in the placement decision.
Lazy database replication with snapshot isolation
TLDR
It is shown how snapshot isolation can be maintained in lazy replicated systems while taking full advantage of the local concurrency controls, and proposed strong session snapshot isolation, a correctness criterion that prevents transaction inversions.
An Experimental Comparison of Pregel-like Graph Processing Systems
TLDR
A study to experimentally compare Giraph, GPS, Mizan, and Graphlab on equal ground by considering graph and algorithm agnostic optimizations and by using several metrics finds that the system optimizations present in Giraph and GraphLab allow them to perform well.
Giraph Unchained: Barrierless Asynchronous Parallel Execution in Pregel-like Graph Processing Systems
TLDR
The results demonstrate that the BAP model provides efficient and transparent asynchronous execution of algorithms that are programmed synchronously, and provides across-the-board performance improvements of up to 5× faster over synchronous systems and up to an order of magnitude faster than asynchronous systems.
Hermes: Dynamic Partitioning for Distributed Social Network Graph Databases
TLDR
This paper introduces a lightweight repartitioner, which dynamically modifies a partitioning using a small amount of resources and integrated it into Hermes, which is designed as an extension of the open source Neo4j graph database system to support workloads over partitioned graph data distributed over multiple servers.
Lazy database replication with ordering guarantees
TLDR
It is shown how generalized strong serializability can be implemented in a lazy replication system, and the results of a simulation study that quantifies the strengths and limitations of the approach are presented.
A taxonomy of decentralized online social networks
TLDR
A number of proposals for peer-to-peer DOSNs are studied, a set of criteria to compare them are distil, and a taxonomy for their comparison is provided.
Generating Efficient Execution Plans for Vertically Partitioned XML Databases
TLDR
This paper proposes a novel technique for constructing distributed execution plans that is independent of local query evaluation strategies, and presents a response time-based cost model that allows us to pick the best execution plan for a given query and database instance.
On the online fault-tolerant server consolidation problem
TLDR
A general lower bound is proved that shows any online algorithm for the online fault-tolerant server consolidation problem has a competitive ratio of at least 1.42, which makes it a good choice for use by cloud service providers.
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