More nit fixes to opentelemetry benches (#1617)

Author: cijothomas

opentelemetry/benches/attributes.rs

@@ -1,5 +1,6 @@
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
-use opentelemetry::KeyValue;
+use opentelemetry::{Key, KeyValue};
+use std::sync::Arc;
 
 // Run this benchmark with:
 // cargo bench --bench attributes
@@ -9,20 +10,38 @@ fn criterion_benchmark(c: &mut Criterion) {
 }
 
 fn attributes_creation(c: &mut Criterion) {
+    c.bench_function("CreateOTelKey_Static", |b| {
+        b.iter(|| {
+            let _v1 = black_box(Key::new("attribute1"));
+        });
+    });
+
+    c.bench_function("CreateOTelKey_Owned", |b| {
+        b.iter(|| {
+            let _v1 = black_box(Key::new(String::from("attribute1")));
+        });
+    });
+
+    c.bench_function("CreateOTelKey_Arc", |b| {
+        b.iter(|| {
+            let _v1 = black_box(Key::new(Arc::from("attribute1")));
+        });
+    });
+
     c.bench_function("CreateOTelKeyValue", |b| {
         b.iter(|| {
             let _v1 = black_box(KeyValue::new("attribute1", "value1"));
         });
     });
 
-    c.bench_function("CreateKeyValueTuple", |b| {
+    c.bench_function("CreateTupleKeyValue", |b| {
         b.iter(|| {
             let _v1 = black_box(("attribute1", "value1"));
         });
     });
 
     #[allow(clippy::useless_vec)]
-    c.bench_function("CreateVector_KeyValue", |b| {
+    c.bench_function("CreateOtelKeyValueVector", |b| {
         b.iter(|| {
             let _v1 = black_box(vec![
                 KeyValue::new("attribute1", "value1"),
@@ -34,7 +53,7 @@ fn attributes_creation(c: &mut Criterion) {
     });
 
     #[allow(clippy::useless_vec)]
-    c.bench_function("CreateVector_StringPairs", |b| {
+    c.bench_function("CreateTupleKeyValueVector", |b| {
         b.iter(|| {
             let _v1 = black_box(vec![
                 ("attribute1", "value1"),

opentelemetry/benches/metrics.rs

@@ -1,15 +1,11 @@
 use criterion::{criterion_group, criterion_main, Criterion};
-use opentelemetry::{
-    metrics::{noop::NoopMeterProvider, Counter, MeterProvider as _},
-    KeyValue,
-};
+use opentelemetry::{global, metrics::Counter, KeyValue};
 
 // Run this benchmark with:
 // cargo bench --bench metrics --features=metrics
 
 fn create_counter() -> Counter<u64> {
-    let meter_provider: NoopMeterProvider = NoopMeterProvider::default();
-    let meter = meter_provider.meter("benchmarks");
+    let meter = global::meter("benchmarks");
     let counter = meter.u64_counter("counter_bench").init();
     counter
 }

opentelemetry/src/global/mod.rs

@@ -127,8 +127,8 @@
 //! pub fn my_traced_library_function() {
 //!     // End users of your library will configure their global meter provider
 //!     // so you can use the global meter without any setup
-//!     let tracer = global::meter("my-library-name");
-//!     let counter = tracer.u64_counter("my_counter").init();
+//!     let meter = global::meter("my-library-name");
+//!     let counter = meter.u64_counter("my_counter").init();
 //!
 //!     // record metrics
 //!     counter.add(1, &[KeyValue::new("mykey", "myvalue")]);