1 vorlesung informatik 2 algorithmen und datenstrukturen (parallel algorithms) robin pomplun
TRANSCRIPT
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Vorlesung Informatik 2
Algorithmen und Datenstrukturen
(Parallel Algorithms)
Robin Pomplun
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Overview
• A simple parallel algorithm
• Analysis of parallel algorithms
• The PRAM model
• The SIMD model
• A parallel Search Algorithm
• A Fast Merging Algorithm
• An efficient Sorting Algorithm
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A simple parallel algorithm
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Analysis of parallel algorithms
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Analysis of parallel algorithms
(Sequential lower bound)
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A work-optimal algorithm
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A work-optimal algorithm
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The PRAM Model
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The PRAM Model
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Classification of the PRAM model
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Classification of the PRAM model
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Models of parallel computation
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The SIMD model
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Design Issues
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Architectures
Hypercube
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Adding n numbers on the mesh
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Adding n numbers on the hypercube
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Parallel Searching, Merging and Sorting
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A parallel search algorithm
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Example
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Example
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Example
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A parallel merge algorithm
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A parallel merge algorithm
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Ranking a short sequence in a sorted sequence
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A fast merging algorithm
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A fast merging algorithm
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Ranking a sample of elements
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A fast merging algorithm
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A fast merging algorithm
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A example
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A fast merging algorithm
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Complexity
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An optimal merging algorithm
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Taking the samples
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An efficient sorting algorithm
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The sequential merge sort algorithm
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An efficient sorting algorithm
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ENDE
Danke für Ihre Aufmerksamkeit !!!