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634
Distributed GraphLab: A Framework for Machine Learning and Data Mining in the Cloud
, 2012
"... While highlevel data parallel frameworks, like MapReduce, simplify the design and implementation of largescale data processing systems, they do not naturally or efficiently support many important data mining and machine learning algorithms and can lead to inefficient learning systems. To help fill ..."
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Cited by 141 (2 self)
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While highlevel data parallel frameworks, like MapReduce, simplify the design and implementation of largescale data processing systems, they do not naturally or efficiently support many important data mining and machine learning algorithms and can lead to inefficient learning systems. To help fill this critical void, we introduced the GraphLab abstraction which naturally expresses asynchronous, dynamic, graphparallel computation while ensuring data consistency and achieving a high degree of parallel performance in the sharedmemory setting. In this paper, we extend the GraphLab framework to the substantially more challenging distributed setting while preserving strong data consistency guarantees. We develop graph based extensions to pipelined locking and data versioning to reduce network congestion and mitigate the effect of network latency. We also introduce fault tolerance to the GraphLab abstraction using the classic ChandyLamport snapshot algorithm and demonstrate how it can be easily implemented by exploiting the GraphLab abstraction itself. Finally, we evaluate our distributed implementation of the GraphLab abstraction on a large Amazon EC2 deployment and show 12 orders of magnitude performance gains over Hadoopbased implementations.
PowerGraph: Distributed GraphParallel Computation on Natural Graphs
"... Largescale graphstructured computation is central to tasks ranging from targeted advertising to natural language processing and has led to the development of several graphparallel abstractions including Pregel and GraphLab. However, the natural graphs commonly found in the realworld have highly ..."
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Cited by 128 (4 self)
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Largescale graphstructured computation is central to tasks ranging from targeted advertising to natural language processing and has led to the development of several graphparallel abstractions including Pregel and GraphLab. However, the natural graphs commonly found in the realworld have highly skewed powerlaw degree distributions, which challenge the assumptions made by these abstractions, limiting performance and scalability. In this paper, we characterize the challenges of computation on natural graphs in the context of existing graphparallel abstractions. We then introduce the PowerGraph abstraction which exploits the internal structure of graph programs to address these challenges. Leveraging the PowerGraph abstraction we introduce a new approach to distributed graph placement and representation that exploits the structure of powerlaw graphs. We provide a detailed analysis and experimental evaluation comparing PowerGraph to two popular graphparallel systems. Finally, we describe three different implementation strategies for PowerGraph and discuss their relative merits with empirical evaluations on largescale realworld problems demonstrating order of magnitude gains. 1
GraphChi: Largescale Graph Computation On just a PC
 In Proceedings of the 10th USENIX conference on Operating Systems Design and Implementation, OSDI’12
, 2012
"... Current systems for graph computation require a distributed computing cluster to handle very large realworld problems, such as analysis on social networks or the web graph. While distributed computational resources have become more accessible, developing distributed graph algorithms still remains c ..."
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Cited by 115 (6 self)
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Current systems for graph computation require a distributed computing cluster to handle very large realworld problems, such as analysis on social networks or the web graph. While distributed computational resources have become more accessible, developing distributed graph algorithms still remains challenging, especially to nonexperts. In this work, we present GraphChi, a diskbased system for computing efficiently on graphs with billions of edges. By using a wellknown method to break large graphs into small parts, and a novel parallel sliding windows method, GraphChi is able to execute several advanced data mining, graph mining, and machine learning algorithms on very large graphs, using just a single consumerlevel computer. We further extend GraphChi to support graphs that evolve over time, and demonstrate that, on a single computer, GraphChi can process over one hundred thousand graph updates per second, while simultaneously performing computation. We show, through experiments and theoretical analysis, that GraphChi performs well on both SSDs and rotational hard drives. By repeating experiments reported for existing distributed systems, we show that, with only fraction of the resources, GraphChi can solve the same problems in very reasonable time. Our work makes largescale graph computation available to anyone with a modern PC. 1
Beyond streams and graphs: Dynamic tensor analysis
 In KDD
, 2006
"... How do we find patterns in authorkeyword associations, evolving over time? Or in DataCubes, with productbranchcustomer sales information? Matrix decompositions, like principal component analysis (PCA) and variants, are invaluable tools for mining, dimensionality reduction, feature selection, rule ..."
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Cited by 113 (16 self)
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How do we find patterns in authorkeyword associations, evolving over time? Or in DataCubes, with productbranchcustomer sales information? Matrix decompositions, like principal component analysis (PCA) and variants, are invaluable tools for mining, dimensionality reduction, feature selection, rule identification in numerous settings like streaming data, text, graphs, social networks and many more. However, they have only two orders, like author and keyword, in the above example. We propose to envision such higher order data as tensors, and tap the vast literature on the topic. However, these methods do not necessarily scale up, let alone operate on semiinfinite streams. Thus, we introduce the dynamic tensor analysis (DTA) method, and its variants. DTA provides a compact summary for highorder and highdimensional data, and it also reveals the hidden correlations. Algorithmically, we designed DTA very carefully so that it is (a) scalable, (b) space efficient (it does not need to store the past) and (c) fully automatic with no need for user defined parameters. Moreover, we propose STA, a streaming tensor analysis method, which provides a fast, streaming approximation to DTA. We implemented all our methods, and applied them in two real settings, namely, anomaly detection and multiway latent semantic indexing. We used two real, large datasets, one on network flow data (100GB over 1 month) and one from DBLP (200MB over 25 years). Our experiments show that our methods are fast, accurate and that they find interesting patterns and outliers on the real datasets. 1.
A Parallel Algorithm for Multilevel Graph Partitioning and Sparse Matrix Ordering
, 1996
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Know your neighbors: Web spam detection using the web topology
 In Proceedings of SIGIR
, 2007
"... Web spam can significantly deteriorate the quality of search engine results. Thus there is a large incentive for commercial search engines to detect spam pages efficiently and accurately. In this paper we present a spam detection system that uses the topology of the Web graph by exploiting the link ..."
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Cited by 108 (9 self)
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Web spam can significantly deteriorate the quality of search engine results. Thus there is a large incentive for commercial search engines to detect spam pages efficiently and accurately. In this paper we present a spam detection system that uses the topology of the Web graph by exploiting the link dependencies among the Web pages, and the content of the pages themselves. We find that linked hosts tend to belong to the same class: either both are spam or both are nonspam. We demonstrate three methods of incorporating the Web graph topology into the predictions obtained by our base classifier: (i) clustering the host graph, and assigning the label of all hosts in the cluster by majority vote, (ii) propagating the predicted labels to neighboring hosts, and (iii) using the predicted labels of neighboring hosts as new features and retraining the classifier. The result is an accurate system for detecting Web spam that can be applied in practice to largescale Web data.
Analysis of multilevel graph partitioning
, 1995
"... Recently, a number of researchers have investigated a class of algorithms that are based on multilevel graph partitioning that have moderate computational complexity, and provide excellent graph partitions. However, there exists little theoretical analysis that could explain the ability of multileve ..."
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Cited by 106 (12 self)
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Recently, a number of researchers have investigated a class of algorithms that are based on multilevel graph partitioning that have moderate computational complexity, and provide excellent graph partitions. However, there exists little theoretical analysis that could explain the ability of multilevel algorithms to produce good partitions. In this paper we present such an analysis. We show under certain reasonable assumptions that even if no refinement is used in the uncoarsening phase, a good bisection of the coarser graph is worse than a good bisection of the finer graph by at most a small factor. We also show that the size of a good vertexseparator of the coarse graph projected to the finer graph (without performing refinement in the uncoarsening phase) is higher than the size of a good vertexseparator of the finer graph by at most a small factor.
Improving Memory Hierarchy Performance for Irregular Applications Using Data and Computation Reorderings
 International Journal of Parallel Programming
, 2001
"... The performance of irregular applications on modern computer systems is hurt by the wide gap between CPU and memory speeds because these applications typically underutilize multilevel memory hierarchies, which help hide this gap. This paper investigates using data and computation reorderings to i ..."
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Cited by 104 (2 self)
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The performance of irregular applications on modern computer systems is hurt by the wide gap between CPU and memory speeds because these applications typically underutilize multilevel memory hierarchies, which help hide this gap. This paper investigates using data and computation reorderings to improve memory hierarchy utilization for irregular applications. We evaluate the impact of reordering on data reuse at different levels in the memory hierarchy. We focus on coordinated data and computation reordering based on spacefilling curves and we introduce a new architectureindependent multilevel blocking strategy for irregular applications. For two particle codes we studied, the most effective reorderings reduced overall execution time by a factor of two and four, respectively. Preliminary experience with a scatter benchmark derived from a large unstructured mesh application showed that careful data and computation ordering reduced primary cache misses by a factor of two compared to a random ordering.
A multilevel banded graph cuts method for fast image segmentation
 In ICCV’05
, 2005
"... In the short time since publication of Boykov and Jolly’s seminal paper [3], graph cuts have become well established as a leading method in 2D and 3D semiautomated image segmentation. Although this approach is computationally feasible for many tasks, the memory overhead and supralinear time complex ..."
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Cited by 92 (5 self)
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In the short time since publication of Boykov and Jolly’s seminal paper [3], graph cuts have become well established as a leading method in 2D and 3D semiautomated image segmentation. Although this approach is computationally feasible for many tasks, the memory overhead and supralinear time complexity of leading algorithms results in an excessive computational burden for highresolution data. In this paper, we introduce a multilevel banded heuristic for computation of graph cuts that is motivated by the wellknown narrow band algorithm in level set computation. We perform a number of numerical experiments to show that this heuristic drastically reduces both the running time and the memory consumption of graph cuts while producing nearly the same segmentation result as the conventional graph cuts. Additionally, we are able to characterize the type of segmentation target for which our multilevel banded heuristic will yield different results from the conventional graph cuts. The proposed method has been applied to both 2D and 3D images with promising results. 1.