Harsha Vardhan Simhadri

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This announcement describes the problem based benchmark suite (PBBS). PBBS is a set of benchmarks designed for comparing parallel algorithmic approaches, parallel programming language styles, and machine architectures across a broad set of problems. Each benchmark is defined concretely in terms of a problem specification and a set of input distributions. No(More)
Perfectly secure message transmission (PSMT), a problem formulated by Dolev, Dwork, Waarts and Yung, involves a sender S and a recipient R who are connected by n synchronous channels of which up to t may be corrupted by an active adversary. The goal is to transmit, with perfect security, a message from S to R. PSMT is achievable if and only if n > 2t. For(More)
In this paper we explore a simple and general approach for developing parallel algorithms that lead to good cache complexity on parallel machines with private or shared caches. The approach is to design nested-parallel algorithms that have low depth (span, critical path length) and for which the natural sequential evaluation order has low cache complexity(More)
The association between social classes, food intake and coronary risk factors was determined. Cross-sectional surveys were conducted in 6-12 urban streets in each of five cities, each one from five different regions of India using similar methods of dietary intakes and criteria of diagnosis. We randomly selected 3257 women aged 25-64 years inclusive, from(More)
For nested-parallel computations with low depth (span, critical path length) analyzing the work, depth, and <i>sequential</i> cache complexity suffices to attain reasonably strong bounds on the <i> parallel</i> runtime and cache complexity on machine models with either shared or private caches. These bounds, however, do not extend to general hierarchical(More)
This paper formalizes and studies <i>combinable memory-block transactions (MBTs)</i>. The idea is to encode short programs that operate on a single cache/memory block and then to specify such a program with a memory request. The code is then executed at the cache or memory controller, atomically with respect to other accesses to that block by this or other(More)
Good locality is critical for the scalability of parallel computations. Many cost models that quantify locality and parallelism of a computation with respect to specific machine models have been proposed. A significant drawback of these machinecentric cost models is their lack of portability. Since the design and analysis of good algorithms in most(More)
OBJECTIVE To study the prevalence of central obesity and age-specific waist:hip ratio of urban women from five Indian cities. DESIGN AND SETTING Cross-sectional surveys were conducted in 6-12 urban streets in different parts of India using similar methods of sample selection and criteria of diagnosis. SUBJECTS AND METHODS We randomly selected 3212(More)
The running time of nested parallel programs on shared-memory machines depends in significant part on how well the scheduler mapping the program to the machine is optimized for the organization of caches and processor cores on the machine. Recent work proposed &#8220;space-bounded schedulers&#8221; for scheduling such programs on the multilevel cache(More)