Update ExponentialHistogram Benchmarks (#4539)

test/Benchmarks/Metrics/Base2ExponentialHistogramBenchmarks.cs

@@ -0,0 +1,128 @@
+// <copyright file="Base2ExponentialHistogramBenchmarks.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// </copyright>
+
+using System.Diagnostics;
+using System.Diagnostics.Metrics;
+using BenchmarkDotNet.Attributes;
+using OpenTelemetry;
+using OpenTelemetry.Metrics;
+using OpenTelemetry.Tests;
+
+/*
+BenchmarkDotNet=v0.13.5, OS=Windows 11 (10.0.23424.1000)
+Intel Core i7-9700 CPU 3.00GHz, 1 CPU, 8 logical and 8 physical cores
+.NET SDK=7.0.203
+  [Host]     : .NET 7.0.5 (7.0.523.17405), X64 RyuJIT AVX2
+  DefaultJob : .NET 7.0.5 (7.0.523.17405), X64 RyuJIT AVX2
+
+
+|                      Method |      Mean |    Error |   StdDev | Allocated |
+|---------------------------- |----------:|---------:|---------:|----------:|
+|            HistogramHotPath |  54.78 ns | 0.907 ns | 0.848 ns |         - |
+|  HistogramWith1LabelHotPath | 115.37 ns | 0.388 ns | 0.363 ns |         - |
+| HistogramWith3LabelsHotPath | 228.03 ns | 3.767 ns | 3.146 ns |         - |
+| HistogramWith5LabelsHotPath | 316.60 ns | 5.980 ns | 9.311 ns |         - |
+| HistogramWith7LabelsHotPath | 366.86 ns | 2.694 ns | 3.596 ns |         - |
+*/
+
+namespace Benchmarks.Metrics;
+
+public class Base2ExponentialHistogramBenchmarks
+{
+    private const int MaxValue = 10000;
+    private readonly Random random = new();
+    private readonly string[] dimensionValues = new string[] { "DimVal1", "DimVal2", "DimVal3", "DimVal4", "DimVal5", "DimVal6", "DimVal7", "DimVal8", "DimVal9", "DimVal10" };
+    private Histogram<long> histogram;
+    private MeterProvider provider;
+    private Meter meter;
+
+    [GlobalSetup]
+    public void Setup()
+    {
+        this.meter = new Meter(Utils.GetCurrentMethodName());
+        this.histogram = this.meter.CreateHistogram<long>("histogram");
+
+        var exportedItems = new List<Metric>();
+
+        this.provider = Sdk.CreateMeterProviderBuilder()
+            .AddMeter(this.meter.Name)
+            .AddInMemoryExporter(exportedItems, metricReaderOptions =>
+            {
+                metricReaderOptions.PeriodicExportingMetricReaderOptions.ExportIntervalMilliseconds = 1000;
+            })
+            .AddView("histogram", new Base2ExponentialBucketHistogramConfiguration())
+            .Build();
+    }
+
+    [GlobalCleanup]
+    public void Cleanup()
+    {
+        this.meter?.Dispose();
+        this.provider?.Dispose();
+    }
+
+    [Benchmark]
+    public void HistogramHotPath()
+    {
+        this.histogram.Record(this.random.Next(MaxValue));
+    }
+
+    [Benchmark]
+    public void HistogramWith1LabelHotPath()
+    {
+        var tag1 = new KeyValuePair<string, object>("DimName1", this.dimensionValues[this.random.Next(0, 2)]);
+        this.histogram.Record(this.random.Next(MaxValue), tag1);
+    }
+
+    [Benchmark]
+    public void HistogramWith3LabelsHotPath()
+    {
+        var tag1 = new KeyValuePair<string, object>("DimName1", this.dimensionValues[this.random.Next(0, 10)]);
+        var tag2 = new KeyValuePair<string, object>("DimName2", this.dimensionValues[this.random.Next(0, 10)]);
+        var tag3 = new KeyValuePair<string, object>("DimName3", this.dimensionValues[this.random.Next(0, 10)]);
+        this.histogram.Record(this.random.Next(MaxValue), tag1, tag2, tag3);
+    }
+
+    [Benchmark]
+    public void HistogramWith5LabelsHotPath()
+    {
+        var tags = new TagList
+            {
+                { "DimName1", this.dimensionValues[this.random.Next(0, 2)] },
+                { "DimName2", this.dimensionValues[this.random.Next(0, 2)] },
+                { "DimName3", this.dimensionValues[this.random.Next(0, 5)] },
+                { "DimName4", this.dimensionValues[this.random.Next(0, 5)] },
+                { "DimName5", this.dimensionValues[this.random.Next(0, 10)] },
+            };
+        this.histogram.Record(this.random.Next(MaxValue), tags);
+    }
+
+    [Benchmark]
+    public void HistogramWith7LabelsHotPath()
+    {
+        var tags = new TagList
+            {
+                { "DimName1", this.dimensionValues[this.random.Next(0, 2)] },
+                { "DimName2", this.dimensionValues[this.random.Next(0, 2)] },
+                { "DimName3", this.dimensionValues[this.random.Next(0, 5)] },
+                { "DimName4", this.dimensionValues[this.random.Next(0, 5)] },
+                { "DimName5", this.dimensionValues[this.random.Next(0, 5)] },
+                { "DimName6", this.dimensionValues[this.random.Next(0, 2)] },
+                { "DimName7", this.dimensionValues[this.random.Next(0, 1)] },
+            };
+        this.histogram.Record(this.random.Next(MaxValue), tags);
+    }
+}

test/Benchmarks/Metrics/ExponentialHistogramMapToIndexBenchmarks.cs → test/Benchmarks/Metrics/Base2ExponentialHistogramMapToIndexBenchmarks.cs

@@ -1,4 +1,4 @@
-// <copyright file="ExponentialHistogramMapToIndexBenchmarks.cs" company="OpenTelemetry Authors">
+// <copyright file="Base2ExponentialHistogramMapToIndexBenchmarks.cs" company="OpenTelemetry Authors">
 // Copyright The OpenTelemetry Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -34,7 +34,7 @@
 
 namespace Benchmarks.Metrics;
 
-public class ExponentialHistogramMapToIndexBenchmarks
+public class Base2ExponentialHistogramMapToIndexBenchmarks
 {
     private const int MaxValue = 10000;
     private readonly Random random = new();

test/Benchmarks/Metrics/ExponentialHistogramBenchmarks.cs → test/Benchmarks/Metrics/Base2ExponentialHistogramScaleBenchmarks.cs

@@ -1,4 +1,4 @@
-// <copyright file="ExponentialHistogramBenchmarks.cs" company="OpenTelemetry Authors">
+// <copyright file="Base2ExponentialHistogramScaleBenchmarks.cs" company="OpenTelemetry Authors">
 // Copyright The OpenTelemetry Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -37,7 +37,7 @@
 
 namespace Benchmarks.Metrics;
 
-public class ExponentialHistogramBenchmarks
+public class Base2ExponentialHistogramScaleBenchmarks
 {
     private const int MaxValue = 10000;
     private readonly Random random = new();