This paper advocates the adaption of external memory algorithms to this purpose. This idea and the practical issues involved are exemplified by engineering a fast priority queue suited to external memory and cached memory that is based on k-way merging. It improves previous external memory algorithms by constant factors crucial for transferring it to cached memory. Running in the cache hierarchy of a workstation the algorithm is at least two times faster than an optimized implementation of binary heaps and 4-ary heaps for large inputs

We describe a model that enables us to analyze the running time of an algorithm in a computer with a memory hierarchy with limited associativity, in terms of various cache parameters. Our model, an extension of Aggarwal and Vitter's I/O model, enables us to establish useful relationships between the cache complexity and the I/O complexity of computations. As a corollary, we obtain cache-optimal algorithms for some fundamental problems like sorting, FFT, and an important subclass of permutations in the single-level cache model. We also show that ignoring associativity concerns could lead to inferior performance, by analyzing the average-case cache behavior of mergesort. We further extend our model to multiple levels of cache with limited associativity and present optimal algorithms for matrix transpose and sorting. Our techniques may be used for systematic exploitation of the memory hierarchy starting from the algorithm design stage, and dealing with the hitherto unresolved problem of l...

Modern computer systems have increasingly complex memory systems.Common machine models for algorithm analysis do not reflect many of the features...

this paper, we focus on one such: the integer sorting algorithm least signicant bit (LSB) radix sort. LSB radix sort sorts w-bit integer keys with an r-bit radix in O(dw=re(n+2

Modern computer systems have increasingly complex memory systems. Common machine models for algorithm analysis do not reflect many of the features of these systems, e.g., large register sets, lockup-free caches, cache hierarchies, associativity, cache line fetching, and streaming behavior. Inadequate models lead to poor algorithmic choices and an incomplete understanding of algorithm behavior on real machines. A key step toward developing better models is to quantify the performance effects of features not reflected in the models. This paper explores the effect of memory system features on sorting performance. We introduce a new cache-conscious sorting algorithm, R-merge, which achieves better performance in practice over algorithms that are superior in the theoretical models. R-merge is designed to minimize memory stall cycles rather than cache misses by considering features common to many system designs.

Abstract not found

We consider the simple problem of scanning multiple sequences. There are k sequences of total length N which are to be scanned concurrently. One pointer into each sequence is maintained and an adversary specifies which pointer is to be advanced. The concept of scanning multiple sequence is ubiquitous in algorithms designed for hierarchical memory.

The paper considers a generalization of the well known random placement of balls into bins.

The paper considers a generalization of the well known random placement of balls into bins. Given n circular arcs of lengths αi, 0 ¡ ¢ i n we study the maximum number of overlapping arcs on a circle if the starting points of the arcs are chosen randomly. We give almost exact tail bounds on the maximum overlap of the arcs. These tail bounds yield a complete characterization of the expected maximum overlap that is tight up to constant factors in the lower order terms. We illustrate the strength of our results by presenting new performance guarantees for several application: Minimizing rotational delays of disks, scheduling accesses to parallel disks and allocating memory to limit cache interference misses.

The paper considers a generalization of the well known random placement of balls into bins. Given n circular arcs of lengths αi, 0 ¡ ¢ i n we study the maximum number of overlapping arcs on a circle if the starting points of the arcs are chosen randomly. We give almost exact tail bounds on the maximum overlap of the arcs. These tail bounds yield a complete characterization of the expected maximum overlap that is tight up to constant factors in the lower order terms. We illustrate the strength of our results by presenting new performance guarantees for several application: Minimizing rotational delays of disks, scheduling accesses to parallel disks and allocating memory to limit cache interference misses.