52 lines
1.4 KiB
Markdown
52 lines
1.4 KiB
Markdown
# Simple/stupid benchmarking
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Compares the string builder and numberToString() function as provided by c++utilities
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with std::stringstream (without reserving stringstream buffer).
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The string builder is actually just a fancy syntax for std::string::reserve()
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making its use more convenient.
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## Compile and run
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eg.
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```
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g++ -O3 stringbuilder-bench.cpp -o stringbuilder-bench-O3 -Wl,-rpath /lib/path -L /lib/path -lc++utilities
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./stringbuilder-bench-O3
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```
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## Results on my machine
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Results with -03:
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```
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plus operator: 00:00:19
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stringstream: 00:00:16
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string builder: 00:00:05
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diff (stringstream minus string builder): 00:00:11
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factor (stringstream / string builder): 3.2
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```
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However, with -O0 4 times *slower*:
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```
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plus operator: 00:00:34
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stringstream: 00:00:23
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string builder: 00:01:02
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diff (stringstream minus string builder): - 00:35:31
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factor (stringstream / string builder): 0.370968
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```
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Still 2.42 times faster than stringstream with -O2:
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```
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plus operator: 00:00:21
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stringstream: 00:00:17
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string builder: 00:00:07
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diff (stringstream minus string builder): 00:00:10
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factor (stringstream / string builder): 2.42857
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```
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So this basic tests show that string builder is up to 2 times faster when using full optimization
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and still 1.4 times faster when using -O2 (default under Arch Linux). However, this templating
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stuff completely relies on optimization (as expected). Results with clang++ where similar.
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