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6013 :: Why nim is slower than other languages(except python) in my test?

• Kiakra (orginal) [2020-03-01T17:35:48+01:00] view original

  https://github.com/Kiakra/test-benchmark/tree/master/test%202

  I think i saw other benchmarks and nim was fast as c in them.

  Why it is much slower compared to LuaJIT and C?

  Is it possible to make it faster?

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• nim_zwei (orginal) [2020-03-01T17:44:59+01:00] view original

  Did you compile your nim file with the -d:release flag?

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• Kiakra (orginal) [2020-03-01T17:48:04+01:00] view original

  Yes, compile options pointed in the benchmark result file

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• Kiakra (orginal) [2020-03-01T17:58:44+01:00] view original

  Nothing changed when added -d:lto flag

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• demotomohiro (orginal) [2020-03-01T18:05:37+01:00] view original

  https://github.com/Kiakra/test-benchmark/blob/master/test 2/main.c https://github.com/Kiakra/test-benchmark/blob/master/test 2/main.nim

  Output from your program is same to the program that quit with do nothing. Modern C/C++ compiler remove any code that doesn't affect outputs. If you want to benchmark how compiler's optimizer optimize your code, output result of calculation to stdout or somewhere.

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• Kiakra (orginal) [2020-03-01T18:12:44+01:00] view original

  I tested what you said (basicly printed(in c printf("%i", a); in nim write(stdout, a)) the variable) And results are so close each other(nim is even faster) C result: (compile: clang -O2)

  Executed in 777.91 millis fish external

  usr time 129.35 millis 213.00 micros 129.14 millis sys time 100.95 millis 63.00 micros 100.89 millis

  nim result: (compile: nim c --cc:clang --opt:speed -d:release)

  Executed in 774.21 millis fish external

  usr time 110.60 millis 227.00 micros 110.37 millis sys time 96.09 millis 69.00 micros 96.02 millis

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• demotomohiro (orginal) [2020-03-01T19:38:08+01:00] view original

  clang can run calculation in following code at compile time and generate a code that only print a number. https://godbolt.org/z/CoNKav

  You need to take some number at runtime and use it in your calculation if you want to run your calculation at runtime. https

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