21 lines
930 B
Markdown
21 lines
930 B
Markdown
# Example 01
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This example compares the timings of adding vectors on the CPU versus adding vectors on the GPU, the latter of which has different implementations.
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## Compiling
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```
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clang++ -std=c++0x -framework OpenCL main.cpp -o main.out
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```
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To ignore deprecation warnings, add the flag `-Wno-deprecated-declarations`.
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Run from this directory, as a relative path is used for the OpenCL header file (for now).
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## About
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The code runs the following implementations of adding large vectors (131072 elements; 8 * 32 * 512). The vectors are added together 10000 times.
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- CPU
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- GPU, where 1024 threads are spawned and each thread thus gets 128 elements to calculate; there are two implementations of this:
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- (Version 1) each thread gets 128 sequential elements (thread 0 gets 0-127, 1 gets 128-255, ...)
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- (Version 2) each thread gets 128 elements, but coalescing happens (thread 0 gets 0,128,256..., thread 1 gets 1,129,257...)
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