1 use criterion::{black_box, criterion_group, criterion_main, Bencher, BenchmarkId, Criterion};
2 use itertools::Itertools;
3 use rand::{rngs::StdRng, seq::SliceRandom, SeedableRng};
4
strict(b: &mut Bencher, (k, vals): &(usize, &Vec<usize>))5 fn strict(b: &mut Bencher, (k, vals): &(usize, &Vec<usize>)) {
6 b.iter(|| black_box(vals.iter()).k_smallest(*k))
7 }
8
relaxed(b: &mut Bencher, (k, vals): &(usize, &Vec<usize>))9 fn relaxed(b: &mut Bencher, (k, vals): &(usize, &Vec<usize>)) {
10 b.iter(|| black_box(vals.iter()).k_smallest_relaxed(*k))
11 }
12
ascending(n: usize) -> Vec<usize>13 fn ascending(n: usize) -> Vec<usize> {
14 (0..n).collect()
15 }
16
random(n: usize) -> Vec<usize>17 fn random(n: usize) -> Vec<usize> {
18 let mut vals = (0..n).collect_vec();
19 vals.shuffle(&mut StdRng::seed_from_u64(42));
20 vals
21 }
22
descending(n: usize) -> Vec<usize>23 fn descending(n: usize) -> Vec<usize> {
24 (0..n).rev().collect()
25 }
26
k_smallest(c: &mut Criterion, order: &str, vals: fn(usize) -> Vec<usize>)27 fn k_smallest(c: &mut Criterion, order: &str, vals: fn(usize) -> Vec<usize>) {
28 let mut g = c.benchmark_group(format!("k-smallest/{order}"));
29
30 for log_n in 20..23 {
31 let n = 1 << log_n;
32
33 let vals = vals(n);
34
35 for log_k in 7..10 {
36 let k = 1 << log_k;
37
38 let params = format!("{log_n}/{log_k}");
39 let input = (k, &vals);
40 g.bench_with_input(BenchmarkId::new("strict", ¶ms), &input, strict);
41 g.bench_with_input(BenchmarkId::new("relaxed", ¶ms), &input, relaxed);
42 }
43 }
44
45 g.finish()
46 }
47
k_smallest_asc(c: &mut Criterion)48 fn k_smallest_asc(c: &mut Criterion) {
49 k_smallest(c, "asc", ascending);
50 }
51
k_smallest_rand(c: &mut Criterion)52 fn k_smallest_rand(c: &mut Criterion) {
53 k_smallest(c, "rand", random);
54 }
55
k_smallest_desc(c: &mut Criterion)56 fn k_smallest_desc(c: &mut Criterion) {
57 k_smallest(c, "desc", descending);
58 }
59
60 criterion_group!(benches, k_smallest_asc, k_smallest_rand, k_smallest_desc);
61 criterion_main!(benches);
62