#include <benchmark/benchmark.h>
#include <thread>

using namespace std::literals;

int v[20]; // sizeof(v[20]) == 80 bytes > cache line

template<int &a, int &b> static void f(benchmark::State &state)
{
    for (auto _: state)
    {
        std::atomic<bool> run = true;
        a = b = 0;
        std::jthread j1([&]{ while (run) ++a; }),
                     j2([&]{ while (run) ++b; });
        std::this_thread::sleep_for(100us);
        run = false;
    }
    state.counters.insert({{"a", a}, {"b", b}});
}

BENCHMARK(f<v[0], v[15]>); // false sharing :(
BENCHMARK(f<v[0], v[16]>); //  true sharing :)

BENCHMARK_MAIN();