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Artigo Revisado por pares

Emanuele Manca, Andrea Manconi, Alessandro Orro, Giuliano Armano, Luciano Milanesi,

... sorting algorithms. Two GPU‐based implementations of the quicksort were presented in literature: the GPU‐quicksort, a compute‐unified device architecture (CUDA) iterative implementation, and the CUDA dynamic parallel (CDP) quicksort, a recursive implementation provided by NVIDIA Corporation. We propose CUDA‐quicksort an iterative GPU‐based implementation of the sorting algorithm. CUDA‐quicksort has been designed starting from GPU‐quicksort. Unlike GPU‐quicksort, it uses atomic primitives to perform inter‐block ...

Tópico(s): Advanced Data Storage Technologies

2015 - Wiley | Concurrency and Computation Practice and Experience

Artigo Acesso aberto Revisado por pares

Martin Aumüller, Martin Dietzfelbinger,

Dual-pivot quicksort refers to variants of classical quicksort where in the partitioning step two pivots are used to split the ... much attention, because it replaced the well-engineered quicksort algorithm in Oracle’s Java 7 runtime library. ... sort an input of size n , beating standard quicksort, which uses 2 n ln n + O ( n ) ... sample, we include a comparison of dual-pivot quicksort and classical quicksort. Specifically, we show that dual-pivot quicksort benefits from a skewed choice of pivots. We ... s algorithm and the recently described 3-pivot quicksort algorithm of Kushagra et al. (ALENEX 2014).

Tópico(s): Error Correcting Code Techniques

2015 - Association for Computing Machinery | ACM Transactions on Algorithms

Artigo Revisado por pares

A. Inkeri Verkamo,

An external sorting algorithm based on quicksort is presented. The file to be sorted is kept on a disk and only those blocks are fetched into the main memory ... performance. When equal block sizes are used, external quicksort results in a much smaller average space requirement ... other hand, mergesort is somewhat faster than external quicksort. The main memory space-time integral of quicksort is always considerably smaller than that of mergesort. External quicksort is less sensitive to the block size and ...

Tópico(s): Computational Physics and Python Applications

1988 - Elsevier BV | Performance Evaluation

Artigo Acesso aberto Revisado por pares

Gerth Stølting Brodal, Rolf Fagerberg, Gabriel Moruz,

Quicksort was first introduced in 1961 by Hoare. Many variants have been developed, the best of which ... algorithms available, as testified by the choice of Quicksort as the default sorting algorithm in most programming ... sorted, according to some specified measure of presortedness. Quicksort is not among these, as it uses Ω( ... demonstrate empirically that the actual running time of Quicksort is adaptive with respect to the presortedness measure ... then show that for the randomized version of Quicksort, the number of element swaps performed is provably ...

Tópico(s): Machine Learning and Algorithms

2008 - Association for Computing Machinery | ACM Journal of Experimental Algorithmics

Artigo Acesso aberto Revisado por pares

Martin Aumüller, Martin Dietzfelbinger, Pascal Klaue,

Multi-Pivot Quicksort refers to variants of classical quicksort where in the partitioning step k pivots are used to split the ... k + 1 segments. For many years, multi-pivot quicksort was regarded as impractical, but in 2009 a ... This article studies what possible advantages multi-pivot quicksort might offer in general. The contributions are as follows: Natural comparison-optimal algorithms for multi-pivot quicksort are devised and analyzed. The analysis shows that ... to predicting observed running times of multi-pivot quicksort algorithms. Finally, it is studied how choosing pivots ...

Tópico(s): VLSI and FPGA Design Techniques

2016 - Association for Computing Machinery | ACM Transactions on Algorithms

Artigo Acesso aberto Revisado por pares

Markus E. Nebel, Sebastian Wild, Conrado Martı́nez,

The new dual-pivot Quicksort by Vladimir Yaroslavskiy—used in Oracle’s Java runtime library since version 7—features intriguing asymmetries. They make a basic ... algorithm use less comparisons than classic single-pivot Quicksort. In this paper, we extend the analysis to ... statistics of a random sample. Surprisingly, dual-pivot Quicksort then needs more comparisons than a corresponding version of classic Quicksort, so it is clear that counting comparisons is ... compared with corresponding versions of classic single-pivot Quicksort, dual-pivot Quicksort needs significantly less I/Os, ...

Tópico(s): Data Management and Algorithms

2015 - Springer Science+Business Media | Algorithmica

Artigo Acesso aberto

Henry G. Baker,

... costs in serial and parallel systems. We programmed Quicksort for both lists and arrays in a "linear" ... of linearity on a serial machine. Even though Quicksort is well-tuned for current non-linear architectures, ... linearity extracts no real penalty. Our "linear" list Quicksort is as fast as any non-linear list Quicksort, and our "linear" vector Quicksort is only 3.5% slower than a non-linear vector Quicksort. The linear style is moderately pleasant, and the ...

Tópico(s): Distributed systems and fault tolerance

1994 - Association for Computing Machinery | ACM SIGPLAN Notices

Artigo Revisado por pares

David Podgorelec, Gregor Klajnšek,

Quicksort is usually the best practical choice for sorting because it is, on average, remarkably efficient. Unfortunately, ... In this paper, we propose a combination of quicksort and a new algorithm, which shows excellent time ... arrays, and which is not much slower than quicksort in random cases. Our work was inspired by ... continue recursively with vertex sort or to employ quicksort in the second iteration. In this way, we ... complexity does not exceed the running times of quicksort, but the simplest cases are handled much faster ( ...

Tópico(s): Computational Geometry and Mesh Generation

2004 - Elsevier BV | Information Sciences

Artigo Revisado por pares

Daniel Cederman, Philippas Tsigas,

In this article, we describe GPU-Quicksort, an efficient Quicksort algorithm suitable for highly parallel multicore graphics processors. Quicksort has previously been considered an inefficient sorting solution for graphics ... for general-purpose computations on graphical processors, GPU-Quicksort performs better than the fastest-known sorting implementations ... graphics processors, such as radix and bitonic sort. Quicksort can thus be seen as a viable alternative ...

Tópico(s): Parallel Computing and Optimization Techniques

2009 - Association for Computing Machinery | ACM Journal of Experimental Algorithmics

Artigo Acesso aberto Revisado por pares

Sebastian Wild, Markus E. Nebel, Ralph Neininger,

... 7 runtime library by a new dual-pivot Quicksort variant due to Vladimir Yaroslavskiy. The decision was ... contrary: previous theoretical studies of other dual-pivot Quicksort variants even discouraged the use of two pivots. ... Bytecode instructions than a simple implementation of classic Quicksort—contradicting observed running times. As in Oracle's ... show that it indeed speeds up Yaroslavskiy's Quicksort in terms of Bytecodes; but even with optimal Insertionsort thresholds, the new Quicksort variant needs slightly more Bytecode instructions on average. ...

Tópico(s): Data Management and Algorithms

2015 - Association for Computing Machinery | ACM Transactions on Algorithms

Artigo Acesso aberto Revisado por pares

Maha Saadeh, Huda Saadeh, Mohammad Qatawneh,

... load balancing algorithms, etc.In this paper, parallel Quicksort, parallel Merge sort, and parallel Merge-Quicksort algorithms are evaluated and compared in terms of ... Results show that the run time of parallel Quicksort algorithm outperforms both Merge sort and Merge-Quicksort algorithms.Moreover, on large number of processors, parallel Quicksort achieves the best parallel efficiency of up to 88%, while Merge sort and Merge-Quicksort algorithms achieve up to 49% and 52% parallel ...

Tópico(s): Network Packet Processing and Optimization

2016 - | International Journal of Advanced Science and Technology

Artigo Revisado por pares

B. Neelima, Bharath Shamsundar, Anjjan S Narayan, R. Prabhu, Crystal Gomes,

... Kepler graphics processing units (GPUs) for multi‐key quicksort. Because multi‐key quicksort is a recursive‐based algorithm, many of the ... idea of matching the template of multi‐key quicksort with the dynamic parallelism feature offered by the ... sort, respectively. The GPU implementation of multi‐key quicksort gives 6× to 18× speed up compared with the CPU parallel implementation of parallel multi‐key quicksort. The GPU implementation of multi‐key quicksort achieves 1.5× to 3× speed up when ...

Tópico(s): Advanced Data Storage Technologies

2016 - Wiley | Concurrency and Computation Practice and Experience

Artigo Revisado por pares

Harold S. Stone,

... CDC STAR computer. One algorithm is Hoare's Quicksort, which is the fastest or nearly the fastest ... A second algorithm is a vector version of Quicksort that takes advantage of the STAR's vector ... a complexity of N log N for the Quicksort algorithms. In spite of its worse complexity, Batcher' ... algorithm is competitive with the serial version of Quicksort for vectors up to the largest that can be treated by STAR. Vector Quicksort outperforms the other two algorithms and is generally ...

Tópico(s): Numerical Methods and Algorithms

1978 - IEEE Computer Society | IEEE Transactions on Software Engineering

Artigo

Daniel Cederman, Philippas Tsigas,

... this paper we take a look at GPU-Quicksort, an efficient Quicksort algorithm suitable for the highly parallel multi-core graphics processors. Quicksort had previously been considered an inefficient sorting solution for graphics processors, but GPU-Quicksort often performs better than the fastest known sorting ... graphics processors, such as radix and bitonic sort. Quicksort can thus be seen as a viable alternative ...

Tópico(s): Advanced Data Storage Technologies

2008 - ACM SIGARCH | ACM SIGARCH Computer Architecture News

Artigo

Syed Mansoor Sarwar, Syed Aqeel Sarwar, M. Jaragh, Jesse Brandeburg,

... study to measure the run-time behavior of Quicksort by using various methods of computing the pivot ... of our study contradict the common notion that Quicksort gives best performance if median of three scheme ... by using insertion sort. It was found that Quicksort performs best when median of three scheme is ... insertion sort can lead to substantial improvements for Quicksort, as conjectured by Sedgewick many years ago.

Tópico(s): VLSI and Analog Circuit Testing

1996 - Elsevier BV | Computer Languages

Capítulo de livro Acesso aberto Revisado por pares

Martin Aumüller, Martin Dietzfelbinger,

Dual pivot quicksort refers to variants of classical quicksort where in the partitioning step two pivots are used to split the ... much attention, because it replaced the well-engineered quicksort algorithm in Oracle’s Java 7 runtime library. ... sort an input of size n, beating standard quicksort, which uses 2nln n + O(n) comparisons. We ...

Tópico(s): Embedded Systems Design Techniques

2013 - Springer Science+Business Media | Lecture notes in computer science

Artigo

Robert Sedgewick,

... a practical study of how to implement the Quicksort sorting algorithm and its best variants on real ... detailed implementation combining the most effective improvements to Quicksort is given, along with a discussion of how ... are considered from a practical standpoint to illustrate Quicksort's wide applicability as an internal sorting method ...

Tópico(s): Algorithms and Data Compression

1978 - Association for Computing Machinery | Communications of the ACM

Artigo Acesso aberto Revisado por pares

R. Geoff Dromey,

Abstract The widely known Quicksort algorithm does not attempt to actively take advantage of partial order in sorting data. A simple change can be made to the Quicksort strategy to give a bestcase performance of n , ... performance of Sedgewick's claimed best implementation of Quicksort for random data.

Tópico(s): DNA and Biological Computing

1984 - Wiley | Software Practice and Experience

Artigo Acesso aberto

Roger L. Wainwright,

Bsort, a variation of Quicksort, combines the interchange technique used in Bubble sort with the Quicksort algorithm to improve the average behavior of Quicksort and eliminate the worst case situation of O( ...

Tópico(s): Data Management and Algorithms

1985 - Association for Computing Machinery | Communications of the ACM

Artigo Revisado por pares

Philip Heidelberger, A. J. Norton, J.T. Robinson,

A parallelization of the Quicksort algorithm that is suitable for execution on a shared memory multiprocessor with an efficient implementation of the fetch-and-add operation is presented. The partitioning phase of Quicksort, which has been considered a serial bottleneck, is ... parallel algorithm maintains the in-place nature of Quicksort, thereby allowing internal sorting of large arrays. A ...

Tópico(s): Distributed and Parallel Computing Systems

1990 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Computers

Artigo Acesso aberto Revisado por pares

P. Hennequin,

... of several characteristic parameters on various forms of Quicksort algorithm: median-of-k, cutting of small lists. ... paramètres caractéristiques de différentes variantes de l'algorithme Quicksort: médiane de k éléments, tri différent sur les ... et les variances des coûts pour l'algorithme Quicksort avec médiane d'un nombre quelconque d'éléments ...

Tópico(s): Constraint Satisfaction and Optimization

1989 - EDP Sciences | RAIRO - Theoretical Informatics and Applications

Artigo Revisado por pares

Michael J. Quinn,

... parallelization; however, since Shellsort has higher complexity than quicksort, parallel Shellsort is inferior to parallel quicksort. A second new parallel algorithm, called quickmerge, is based upon both quicksort and mergesort. Our implementation of quickmerge achieves significantly higher speedup than occur implementation of parallel quicksort.

Tópico(s): Parallel Computing and Optimization Techniques

1988 - Elsevier BV | Parallel Computing

Artigo Revisado por pares

Dalia Motzkin,

Abstract A sorting algorithm, called Stable Quicksort, is presented. the algorithm is comparable in speed with the Quicksort algorithm, but is stable. The experimental evidence presented support the theoretical evaluation of the performance of Stable Quicksort.

Tópico(s): Blind Source Separation Techniques

1981 - Wiley | Software Practice and Experience

Artigo Acesso aberto Revisado por pares

Michael Cramer,

... obtain information on the limit distribution of the Quicksort algorithm.This distribution is also correlated to the ... not the same.Résumé.-La distribution limite de Quicksort (qui est la même que la distribution limite ... de quelques moments, que la distribution limite de Quicksort n 'est pas log-normale.

Tópico(s): Diffusion and Search Dynamics

1996 - EDP Sciences | RAIRO - Theoretical Informatics and Applications

Artigo Revisado por pares

Catherine C. McGeoch, J. D. Tygar,

Abstract A well‐known improvement on the basic Quicksort algorithm is to sample from the subarray at ... cost measure are new to the analysis of Quicksort. A square‐root strategy, which takes a sample ... exact optimal strategy for a standard implementation of Quicksort is found computationally for n below 3000. © 1995 ...

Tópico(s): Machine Learning and Data Classification

1995 - Wiley | Random Structures and Algorithms

Artigo Acesso aberto Revisado por pares

Mahmoud Fouz, Manfred Kufleitner, Bodo Manthey, Nima Zeini Jahromi,

... algorithm, and we revisit the smoothed analysis of quicksort. Hoare’s find algorithm—often called quickselect or one-sided quicksort—is an easy-to-implement algorithm for finding ... bounds for the smoothed number of comparisons of quicksort and Hoare’s find for the median-of- ...

Tópico(s): Computational Geometry and Mesh Generation

2011 - Springer Science+Business Media | Algorithmica

Artigo Acesso aberto Revisado por pares

Vasileios Iliopoulos, David Penman,

In this paper, we analyse the dual pivot Quicksort, a variant of the standard Quicksort algorithm, in which two pivots are used for ... comparisons. In terms of mean values, dual pivot Quicksort does not appear to be faster than ordinary ...

Tópico(s): Evolutionary Algorithms and Applications

2012 - World Scientific | Discrete Mathematics Algorithms and Applications

Artigo Acesso aberto Revisado por pares

Conrado Martı́nez, Uwe Rösler,

Partial Quicksort sorts the $l$ smallest elements in a list of length $n$. We provide a complete running time analysis for this combination of Find and Quicksort. Further we give some optimal adapted versions, called Partition Quicksort, with an asymptotic running time $c_1l\ln ...

Tópico(s): Computational Geometry and Mesh Generation

2010 - French association | Discrete Mathematics & Theoretical Computer Science

Artigo Acesso aberto Revisado por pares

Mireille Régnier,

... distribution for the number of comparisons performed by quicksort, ot, equivalently, for the external path length of ... limite pour le nombre de comparaisons effectuées par quicksort, ou, de manière équivalente, pour la longueur de ...

Tópico(s): Bayesian Methods and Mixture Models

1989 - EDP Sciences | RAIRO - Theoretical Informatics and Applications

Capítulo de livro Acesso aberto Revisado por pares

Brigitte Vallée, Julien Clément, James Allen Fill, Philippe Flajolet,

We revisit the classical QuickSort and QuickSelect algorithms, under a complexity model that fully takes into account the elementary comparisons between symbols composing the records ... under our conditions, the average-case complexity of QuickSort is O(nlog2 n) [rather than O(nlogn), ...

Tópico(s): Advanced Image and Video Retrieval Techniques

2009 - Springer Science+Business Media | Lecture notes in computer science