[dev-dependencies]
criterion = "0.5"

[[bench]]
name = "my_bench"
harness = false

// benches/my_bench.rs
use criterion::{black_box, criterion_group, criterion_main, Criterion, BenchmarkId};

fn fibonacci_recursive(n: u64) -> u64 {
    match n {
        0 | 1 => n,
        _ => fibonacci_recursive(n - 1) + fibonacci_recursive(n - 2),
    }
}

fn fibonacci_iterative(n: u64) -> u64 {
    let (mut a, mut b) = (0, 1);
    for _ in 0..n {
        let temp = a + b;
        a = b;
        b = temp;
    }
    a
}

fn bench_fibonacci(c: &mut Criterion) {
    let mut group = c.benchmark_group("fibonacci");

    for n in [10, 20, 30] {
        group.bench_with_input(
            BenchmarkId::new("recursive", n),
            &n,
            |b, &n| b.iter(|| fibonacci_recursive(black_box(n))),
        );
        group.bench_with_input(
            BenchmarkId::new("iterative", n),
            &n,
            |b, &n| b.iter(|| fibonacci_iterative(black_box(n))),
        );
    }

    group.finish();
}

criterion_group!(benches, bench_fibonacci);
criterion_main!(benches);

cargo bench

# 查看报告
open target/criterion/report/index.html

use criterion::{Criterion, SamplingMode};

fn bench_config(c: &mut Criterion) {
    let mut group = c.benchmark_group("my_group");
    group.sample_size(100);        // 采样次数
    group.sampling_mode(SamplingMode::Flat);
    group.measurement_time(std::time::Duration::from_secs(5));

    group.bench_function("my_fn", |b| {
        b.iter(|| { /* ... */ })
    });

    group.finish();
}