Using Prime Numbers for Cache Indexing to Eliminate Conflict Misses, HPCA

Using alternative cache indexing/hashing functions is a popular technique to reduce conflict misses by achieving a more uniform cache access distribution across the sets in the cache. Although various alternative hashing functions have been demonstrated to eliminate the worst case conflict behavior, no study has really analyzed the pathological behavior of such hashing functions that often result in performance slowdown. In this paper, we present an in-depth analysis of the pathological behavior of cache hashing functions. Based on the analysis, we propose two new hashing functions: prime modulo and prime displacement that are resistant to pathological behavior and yet are able to eliminate the worst case conflict behavior in the L2 cache. We show that these two schemes can be implemented in fast hardware using a set of narrow add operations, with negligible fragmentation in the L2 cache. We evaluate the schemes on 23 memory intensive applications. For applications that have non-uniform cache accesses, both prime modulo and prime displacement hashing achieve an average speedup of 1.27 compared to traditional hashing, without slowing down any of the 23 benchmarks. We also evaluate using multiple prime displacement hashing functions in conjunction with a skewed associative L2 cache. The skewed associative cache achieves a better average speedup at the cost of some pathological behavior that slows down four applications by up to 7%. 1

A toolset of image processing algorithms for forensic document examination

One of the tasks of a forensic document examiner is to analyse the authorship of a handwritten document. The purpose of such analysis is to determine whether a document has been forged (forgery identification), to determine whether an author has tried to disguise his handwriting (disguised writing identification), or to identify the author of a document (writer identification).Master of Applied Scienc

Fundamentals of parallel multicore architecture/ Solihin

xxvi, p.468.: ill.; 26 c

Fundamentals of parallel multicore architecture/ Solihin

xxvi, p.468.: ill.; 26 c

Improving Memory Performance Using Intelligent Memory

102 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2002.Alternatively, the memory can directly execute memory-intensive code sections. We propose a compiler and run-time algorithm to break out the code into sections with uniform memory and compute behavior. These sections are statically or dynamically mapped on the memory or the main processor based on their affinity. In addition, processor and memory overlap their execution as much as possible. We show that the resulting speedups are close and often higher than ideal speedups on a more expensive machine with two identical main processors.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Grey-Scale Image Thresholding for Specific Applications

Summary. A thresholding approach that performs thresholding stage by stage on grey scale images is discussed. The ability to exploit various information from the image to assist the assignment of a threshold level is central to the multi-stage approach. Thus it is better suited to images that have consistent characteristics as encountered in specific applications. In the traditional global thresholding approach, one threshold value is produced in a single stage to separate an object from its background in an image. In the multi-stage global thresholding approach, each stage in the thresholding uses various information from the image to narrow the search space until the last stage selects the single threshold value. In the traditional local (adaptive) thresholding approach, thresholding is performed in one pass using local information obtained from the image. In the multi-stage local thresholding approach, thresholding is performed in several passes (stages) using different information from the image at each stage. Two examples taken from the literature, Quadratic Integral Ratio, which was designed by the authors to threshold handwriting images and Chi and Yan’s technique, which was designed to threshold map images, are used to demonstrate how this approach can be used in specific applications, producing better results compared to traditional thresholding techniques. The multi-stage thresholding approach will be useful in promoting the invention of new high performance application-specific thresholding techniques