Journal ArticleDOI
Scheduling multithreaded computations by work stealing
TLDR
This paper gives the first provably good work-stealing scheduler for multithreaded computations with dependencies, and shows that the expected time to execute a fully strict computation on P processors using this scheduler is 1:1.Abstract:
This paper studies the problem of efficiently schedulling fully strict (i.e., well-structured) multithreaded computations on parallel computers. A popular and practical method of scheduling this kind of dynamic MIMD-style computation is “work stealing,” in which processors needing work steal computational threads from other processors. In this paper, we give the first provably good work-stealing scheduler for multithreaded computations with dependencies.Specifically, our analysis shows that the expected time to execute a fully strict computation on P processors using our work-stealing scheduler is T1/P + O(T ∞ , where T1 is the minimum serial execution time of the multithreaded computation and (T ∞ is the minimum execution time with an infinite number of processors. Moreover, the space required by the execution is at most S1P, where S1 is the minimum serial space requirement. We also show that the expected total communication of the algorithm is at most O(PT ∞( 1 + nd)Smax), where Smax is the size of the largest activation record of any thread and nd is the maximum number of times that any thread synchronizes with its parent. This communication bound justifies the folk wisdom that work-stealing schedulers are more communication efficient than their work-sharing counterparts. All three of these bounds are existentially optimal to within a constant factor.read more
Citations
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Book ChapterDOI
Efficient Wavelet Tree Construction and Querying for Multicore Architectures
TL;DR: Two practical multicore algorithms for wavelet tree construction that run in O(n) time using $\lg \sigma$ processors, where n is the size of the input and σ the alphabet size, and have efficient memory consumption are introduced.
Proceedings ArticleDOI
Hybrid Static/dynamic Scheduling for Already Optimized Dense Matrix Factorization
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Software Development Lifecycle for Energy Efficiency: Techniques and Tools
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Journal ArticleDOI
A Visual Performance Analysis Framework for Task-based Parallel Applications running on Hybrid Clusters
Vinicius Garcia Pinto,Vinicius Garcia Pinto,Lucas Mello Schnorr,Lucas Mello Schnorr,Luka Stanisic,Arnaud Legrand,Samuel Thibault,Vincent Danjean +7 more
TL;DR: A flexible framework that enables one to combine several sources of information and to create custom visualization panels allowing to understand and pinpoint performance problems incurred by bad scheduling decisions in task‐based applications is presented.
Journal ArticleDOI
Open problems in queueing theory inspired by datacenter computing
TL;DR: In this paper, the authors expose queueing theorists to new models, while providing suggestions for many specific open problems of interest, as well as some insights into their potential solution, and expose queuing theory to new service-level objectives in terms of tail probabilities.
References
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Journal ArticleDOI
Cilk: An Efficient Multithreaded Runtime System
Robert D. Blumofe,Christopher F. Joerg,Bradley C. Kuszmaul,Charles E. Leiserson,Keith H. Randall,Yuli Zhou +5 more
TL;DR: It is shown that on real and synthetic applications, the “work” and “critical-path length” of a Cilk computation can be used to model performance accurately, and it is proved that for the class of “fully strict” (well-structured) programs, the Cilk scheduler achieves space, time, and communication bounds all within a constant factor of optimal.
Journal ArticleDOI
Bounds for certain multiprocessing anomalies
TL;DR: In this paper, precise bounds are derived for several anomalies of this type in a multiprocessing system composed of many identical processing units operating in parallel, and they show that an increase in the number of processing units can cause an increased total length of time needed to process a fixed set of tasks.
Proceedings ArticleDOI
The implementation of the Cilk-5 multithreaded language
TL;DR: Cilk-5's novel "two-clone" compilation strategy and its Dijkstra-like mutual-exclusion protocol for implementing the ready deque in the work-stealing scheduler are presented.
Journal ArticleDOI
The Parallel Evaluation of General Arithmetic Expressions
TL;DR: It is shown that arithmetic expressions with n ≥ 1 variables and constants; operations of addition, multiplication, and division; and any depth of parenthesis nesting can be evaluated in time 4 log 2 + 10(n - 1) using processors which can independently perform arithmetic operations in unit time.