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added C++ measurements

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This commit is contained in:
Richard Thier 2025-04-03 15:29:28 +02:00
parent 40da271e34
commit a6dd3f93cd
1 changed files with 33 additions and 1 deletions
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34
perf.cpp
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@ -2,6 +2,7 @@
#include <cstdlib>
#include <chrono>
#include <cassert>
#include <random>
#include "fastrand.h"
#define N 10000000
@ -22,6 +23,10 @@ int main() {
srand((unsigned int)time(NULL));
rand_state rs = init_rand();
rand_ilp_state rs_ilp = init_rand_ilp();
// C++ engines
std::linear_congruential_engine<uint32_t, 1664525u, 1013904223u, 0> lce;
std::mt19937 mte;
std::minstd_rand lce_def;
// Generate FROM,TO as random, because otherwise compiler optimizes out IDIV of the '%' operator!
uint32_t FROM = (uint32_t) rand();
@ -45,6 +50,27 @@ int main() {
auto t2 = std::chrono::high_resolution_clock::now();
// C++ LCG
for (int i = 0; i < N; ++i) {
res[i] += lce_def();
}
auto t21 = std::chrono::high_resolution_clock::now();
// C++ LCG - my parameters
for (int i = 0; i < N; ++i) {
res[i] += lce();
}
auto t211 = std::chrono::high_resolution_clock::now();
// C++ MT
for (int i = 0; i < N; ++i) {
res[i] += mte();
}
auto t22 = std::chrono::high_resolution_clock::now();
// lcg
for (int i = 0; i < N; ++i) {
res[i] += lcg(&rs);
@ -65,11 +91,17 @@ int main() {
auto arc4_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t1 - t0);
auto rand_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t2 - t1);
auto lcg_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t3 - t2);
auto lce_def_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t21 - t2);
auto lce_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t211 - t21);
auto mt_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t22 - t21);
auto lcg_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t3 - t22);
auto lcg4_elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(t31 - t3);
printf("Time (arc4): %.3f ms.\n", arc4_elapsed.count() * 1e-6);
printf("Time (rand): %.3f ms.\n", rand_elapsed.count() * 1e-6);
printf("Time (C++ lcg): %.3f ms.\n", lce_def_elapsed.count() * 1e-6);
printf("Time (C++ lcg my parameters): %.3f ms.\n", lce_elapsed.count() * 1e-6);
printf("Time (C++ mersenne twister 32bit): %.3f ms.\n", mt_elapsed.count() * 1e-6);
printf("Time (lcg): %.3f ms.\n", lcg_elapsed.count() * 1e-6);
printf("Time (lcg4): %.3f ms.\n", lcg4_elapsed.count() * 1e-6);