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CPS615 -- Base Course for the Simulation Track of Computational Science Fall Semester 1997 -- The Laplace Example Programming and Performance 2
Abstract of Laplace Example for CPS615 3
Parallel Computing Algorithms and Software -- Laplace Example 4
The Solution of Laplace's Equation 5
Discretized Form of Laplace'e Equation on a Parallel Processor 6
Basic Structure of Domain to be Updated in Parallel Version 7
Sequential and Introduction to Parallel Coding for the Laplace Example 8
SEQUENTIAL LAPLACE PROGRAMMING JACOBI ITERATION IN ONE DIMENSION (constant in y direction) 9
SEQUENTIAL LAPLACE PROGRAMMING JACOBI ITERATION IN TWO DIMENSIONS 10
Approaches to Parallel Programming 11
SPMD or SCMD Single Program (code) Multiple Data 12
Data Parallel Programming for Laplace Example 13
Parallel Laplace Programming Data Parallel for Jacobi Iteration in One Dimension 14
Notes on HPF Implementation of Lapace Solver 15
Message Passing Model Used for Parallel Programming for Laplace Example 16
Basic Message Passing Approach 17
Various Styles/Terms in Messaging Passing - I 18
Various Styles/Terms in Messaging Passing - II 19
Parallel Laplace Programming: Set Up of Message Passing for Jacobi Iteration in One Dimension 20
Node Program: Message Passing for Laplace Sover 21
Collective Communication Primitives 22
Implementation of MPSHIFT(+1, SOURCE,DEST) 23
Possible Implementation of MPSHIFT in MPI 24
Implementation of SHIFT in MPI 25
Implementation of GLOBALMAX (TEST) 26
General Features of Laplace Example 27
What does the Laplace Update calculation look like? 28
The Various Stencil Special Cases 29
Communication Loads 30
What is the relation of sequential and parallel programming models ? 31
More on SPMD Programming Model and Sequential/Parallel Comparison 32
Programming with Guard Rings - Sequential 33
Programming with Guard Rings - Parallel 34
Special Case of Corner Processor 35
Analysis of Parallel Overheads Efficiency and Speedup 36
General Formalism for Speed Up 37
What Affects Speed Up ? 38
Load Imbalance and Speed-Up for Laplace Example -- I 39
Load Imbalance and Speed-Up for Laplace Example -- II 40
Analytical Analysis of Load Imbalance 41
Communication Overhead 42
Analytical Form of Speed Up for Communication Overhead 43
General Form of Efficiency 44
Communication to Calculation Ratio as a function of template 45
Performance for Increasing Stencil 46
Matrix Multiplication on the Hypercube 47
Efficiency of QCD Physics Simulation on JPL MarkIIIfp Hypercube 48
General Analysis of Overheads and Efficiency 49
Speed Up as a Function of Grain Size
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