Kristyn J. Maschhoff

Learn More
This paper describes our early experiences with a pre- production Cray XMT system that implements a scalable shared memory architecture with hardware support for multithreading. Unlike its predecessor, the Cray MTA-2 that had very limited I/O capability, the Cray XMT offers Lustre, a scalable high-performance parallel filesystem. Therefore it enables(More)
Commonly represented as directed graphs, social networks depict relationships and behaviors among social entities such as people, groups, and organizations. Social network analysis denotes a class of mathematical and statistical methods designed to study and measure social networks. Beyond sociology, social network analysis methods are being applied to(More)
Several 64-processor XMT systems have now been shipped to customers and there have been 128-processor, 256-processor and 512-processor systems tested in Cray's development lab. We describe some techniques we have used for tuning performance in hopes that applications continued to scale on these larger systems. We discuss how the programmer must work with(More)
We explore the trade-offs of performing linear algebra using Apache Spark, compared to traditional C and MPI implementations on HPC platforms. Spark is designed for data analytics on cluster computing platforms with access to local disks and is optimized for data-parallel tasks. We examine three widely-used and important matrix factorizations: NMF (for(More)
String searching is at the core of many security and network applications like search engines, intrusion detection systems, virus scanners and spam filters. The growing size of on-line content and the increasing wire speeds push the need for fast, and often real-time, string searching solutions. For these conditions, many software implementations (if not(More)
The Berkeley Data Analytics Stack (BDAS) is an emerging framework for big data analytics. It consists of the Spark analytics framework, the Tachyon in-memory filesystem, and the Mesos cluster manager. Spark was designed as an in-memory replacement for Hadoop that can in some cases improve performance by up to 100X. In this paper, we describe our experiences(More)
Much of the early domain-specific success with graph analytics has been with algorithms whose results are based on global graph structure. An example of such an algorithm is betweenness centrality, whose value for any vertex potentially depends on the number of shortest paths between all pairs of vertices in the entire graph. YarcData's Urika<sup>TM</sup>(More)
We explore the trade-offs of performing linear algebra using Apache Spark, compared to traditional C and MPI implementations on HPC platforms. Spark is designed for data analytics on cluster computing platforms with access to local disks and is optimized for data-parallel tasks. We examine three widely-used and important matrix factorizations: NMF (for(More)