bench: crossbeam benchmark use the same group so we can directly compare lockless vs mutex

bench/crossbeam.rs

@@ -29,7 +29,7 @@ use std::{
 };
 
 fn crossbeam(c: &mut Criterion) {
-    let mut group = c.benchmark_group("crossbeam");
+    let mut group = c.benchmark_group("crossbeam_vs_mutex-hashmap");
 
     for k in 1..10 {
         let stopped = Arc::new(AtomicBool::new(false));
@@ -54,7 +54,7 @@ fn crossbeam(c: &mut Criterion) {
                 .run();
         });
 
-        group.bench_with_input(BenchmarkId::from_parameter(k), &k, |b, &_| {
+        group.bench_with_input(BenchmarkId::new("crossbeam", k), &k, |b, &_| {
             b.iter_batched(
                 || {
                     let key: usize = OsRng.gen();
@@ -62,7 +62,6 @@ fn crossbeam(c: &mut Criterion) {
                     (key, val)
                 },
                 |(key, val)| {
-                    // Do 10k inserts
                     map.insert(key, val);
                 },
                 BatchSize::SmallInput,
@@ -73,12 +72,9 @@ fn crossbeam(c: &mut Criterion) {
         parallel_inserts.join().unwrap();
     }
 
-    group.finish();
-
     // Now try normal Mutex hashmap
     // This is not an async Mutex, but async Mutexes are always slower than sync ones anyway
     // since they just implement an async interface on top of sync Mutexes.
-    let mut group = c.benchmark_group("mutex_hashmap");
 
     for k in 1..10 {
         let stopped = Arc::new(AtomicBool::new(false));
@@ -103,7 +99,7 @@ fn crossbeam(c: &mut Criterion) {
                 .run();
         });
 
-        group.bench_with_input(BenchmarkId::from_parameter(k), &k, |b, &_| {
+        group.bench_with_input(BenchmarkId::new("mutex_hashmap", k), &k, |b, &_| {
             b.iter_batched(
                 || {
                     let key: usize = OsRng.gen();
@@ -111,7 +107,6 @@ fn crossbeam(c: &mut Criterion) {
                     (key, val)
                 },
                 |(key, val)| {
-                    // Do 10k inserts
                     map.lock().unwrap().insert(key, val);
                 },
                 BatchSize::SmallInput,
@@ -121,8 +116,6 @@ fn crossbeam(c: &mut Criterion) {
         stopped.store(true, Ordering::Relaxed);
         parallel_inserts.join().unwrap();
     }
-
-    group.finish();
 }
 
 criterion_group!(bench, crossbeam);