CS代考计算机代写 Assignment 1 – OpenMP

Assignment 1 – OpenMP
 Use OpenMP to parallelize the deqn code
• The overall objective is to achieve good speedup by inserting OpenMP directives in the deqn code
 Speed up is the ratio of the execution time of the sequential version of a program to the execution time of the parallel version of the program
 You also need to
• benchmark the runtime of each relevant loop and the runtime of the
whole parallel program against the number ofthreads
• benchmark the overhead of OpenMP
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Assignment 1 – OpenMP  Write a report
• Explain in detail what you did with the sequentialcode
• benchmark the runtime of each relevant loop and the runtime of the whole parallel program against the number of threads; present the runtimes in graph or table; analyze the results
• Discuss the iteration scheduling in your program
• Analyze the overhead of OpenMP
• Presentation skills, spelling, punctuation and grammar
• Up to four A4 pages
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Submission
– Put all the codes and the report (pdf file) in a zip package and submit the zip package through Tabula
– Deadline: 12 noon, Feb 9th, 2021

deqn
 Model the transfer of heat through a material
 Expressed as a partial differential equation, where u is the temperature, which is the function over coordinates x and y, and time t
 Use the numerical method to solve the equation, i.e, obtain the values of u at coordinates (x, y) and at time points t
• Discretize the space and the time
Discretize the time
Discretize the space
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deqn
 Model the transfer of heat through a material
 Expressed as a partial differential equation, where u is the temperature , x and y are coordinates
 Use the numerical method to solve the equation, i.e, obtain the values of u at the coordinates (x, y) and at the time point t
• Discretize the space and the time
• Convert partial differential equation to linear equation
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Convert partial differential equation to linear equation

Data Dependency
ux-h,y
ux,y-h
ux,y
ux,y+h
ux+h,y
t
ux-h,y
ux,y
ux+h,y
ux,y+h
t+k
Question: How to parallelize the computation?
time
Given the initial temperature of the material, we can calculate the temperature of the material at any time point and space location
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Parallelism
Thread 1 Thread 2
Ux,y-1
Ux-1,y
Ux,y
Ux+1,y
Ux,y+1
• Each thread calculates the temperature at any time and at its local space in parallel
• Thread communication
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