research-article

Compiler-assisted dynamic scheduling for effective parallelization of loop nests on multicore processors

Authors:

Muthu Manikandan Baskaran,

Nagavijayalakshmi Vydyanathan,

Uday Kumar Reddy Bondhugula,

Atanas Rountev,

P. SadayappanAuthors Info & Claims

PPoPP '09: Proceedings of the 14th ACM SIGPLAN symposium on Principles and practice of parallel programming

Pages 219 - 228

https://doi.org/10.1145/1504176.1504209

Published: 14 February 2009 Publication History

Abstract

Recent advances in polyhedral compilation technology have made it feasible to automatically transform affine sequential loop nests for tiled parallel execution on multi-core processors. However, for multi-statement input programs with statements of different dimensionalities, such as Cholesky or LU decomposition, the parallel tiled code generated by existing automatic parallelization approaches may suffer from significant load imbalance, resulting in poor scalability on multi-core systems. In this paper, we develop a completely automatic parallelization approach for transforming input affine sequential codes into efficient parallel codes that can be executed on a multi-core system in a load-balanced manner. In our approach, we employ a compile-time technique that enables dynamic extraction of inter-tile dependences at run-time, and dynamic scheduling of the parallel tiles on the processor cores for improved scalable execution. Our approach obviates the need for programmer intervention and re-writing of existing algorithms for efficient parallel execution on multi-cores. We demonstrate the usefulness of our approach through comparisons using linear algebra computations: LU and Cholesky decomposition.

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Index Terms

Compiler-assisted dynamic scheduling for effective parallelization of loop nests on multicore processors
1. Software and its engineering
  1. Software notations and tools
    1. Compilers
      1. Runtime environments
      2. Source code generation

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cover image ACM Conferences

PPoPP '09: Proceedings of the 14th ACM SIGPLAN symposium on Principles and practice of parallel programming

February 2009

322 pages

ISBN:9781605583976

DOI:10.1145/1504176

General Chair:
Daniel Reed
Microsoft Research, USA
,
Program Chair:
Vivek Sarkar
Rice University, USA

ACM SIGPLAN Notices Volume 44, Issue 4
PPoPP '09
April 2009
294 pages
ISSN:0362-1340
EISSN:1558-1160
DOI:10.1145/1594835
Issue’s Table of Contents

Copyright © 2009 ACM.

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Published: 14 February 2009

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https://dl.acm.org/doi/10.1109/SC.2018.00065
Baroudi TSeghir RLoechner V(2017)Optimization of Triangular and Banded Matrix Operations Using 2d-Packed LayoutsACM Transactions on Architecture and Code Optimization10.1145/316201614:4(1-19)Online publication date: 18-Dec-2017
https://dl.acm.org/doi/10.1145/3162016
Dathathri RMullapudi RBondhugula U(2016)Compiling Affine Loop Nests for a Dynamic Scheduling Runtime on Shared and Distributed MemoryACM Transactions on Parallel Computing10.1145/29489753:2(1-28)Online publication date: 20-Jul-2016
https://dl.acm.org/doi/10.1145/2948975
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