[Instrumentation.Process] Exposed required metric process.cpu.count for computing CPU utilization in the backend.

src/OpenTelemetry.Instrumentation.Process/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+* Added `process.cpu.count` metric.
+ ([#981](https:/open-telemetry/opentelemetry-dotnet-contrib/pull/981))
+
 ## 1.0.0-alpha.6
 
 Released 2023-Feb-13

src/OpenTelemetry.Instrumentation.Process/ProcessMetrics.cs

@@ -16,6 +16,7 @@
 
 #nullable enable
 
+using System;
 using System.Collections.Generic;
 using System.Diagnostics.Metrics;
 using System.Reflection;
@@ -64,6 +65,15 @@ static ProcessMetrics()
  unit: "s",
  description: "Total CPU seconds broken down by different states.");
 
+ MeterInstance.CreateObservableUpDownCounter(
+ "process.cpu.count",
+ () =>
+ {
+ return Environment.ProcessorCount;
+ },
+ unit: "{processors}",
+ description: "The number of processors (CPU cores) available to the current process.");
+
  MeterInstance.CreateObservableUpDownCounter(
  "process.threads",
  () =>

src/OpenTelemetry.Instrumentation.Process/README.md

@@ -92,6 +92,20 @@ Gets the user processor time for this process.
 * [Process.PrivilegedProcessorTime](https://learn.microsoft.com/dotnet/api/system.diagnostics.process.privilegedprocessortime):
 Gets the privileged processor time for this process.
 
+### process.cpu.count
+
+The number of processors (CPU cores) available to the current process.
+
+| Units | Instrument Type | Value Type |
+|---------------|-------------------------|------------|
+| `{processors}`| ObservableUpDownCounter | `Int32` |
+
+The API used to retrieve the value is:
+
+* [Process.processors](https://learn.microsoft.com/dotnet/api/system.environment.processorcount):
+Gets the number of processors available
+to the current process.
+
 ### process.threads
 
 Process threads count.

test/OpenTelemetry.Instrumentation.Process.Tests/ProcessMetricsTests.cs

@@ -38,14 +38,16 @@ public void ProcessMetricsAreCaptured()
 
  meterProviderA.ForceFlush(MaxTimeToAllowForFlush);
 
- Assert.True(exportedItemsA.Count == 4);
+ Assert.True(exportedItemsA.Count == 5);
  var physicalMemoryMetric = exportedItemsA.FirstOrDefault(i => i.Name == "process.memory.usage");
  Assert.NotNull(physicalMemoryMetric);
  var virtualMemoryMetric = exportedItemsA.FirstOrDefault(i => i.Name == "process.memory.virtual");
  Assert.NotNull(virtualMemoryMetric);
  var cpuTimeMetric = exportedItemsA.FirstOrDefault(i => i.Name == "process.cpu.time");
  Assert.NotNull(cpuTimeMetric);
- var threadMetric = exportedItemsA.FirstOrDefault(i => i.Name == "process.threads");
+ var processorCountMetric = exportedItemsA.FirstOrDefault(i => i.Name == "process.cpu.count");
+ Assert.NotNull(processorCountMetric);
+ var threadMetric = exportedItemsA.FirstOrDefault(i => i.Name == "process.cpu.count");
  Assert.NotNull(threadMetric);
 
  exportedItemsA.Clear();
@@ -66,8 +68,8 @@ public void ProcessMetricsAreCaptured()
 
  meterProviderB.ForceFlush(MaxTimeToAllowForFlush);
 
- Assert.True(exportedItemsA.Count == 4);
- Assert.True(exportedItemsB.Count == 4);
+ Assert.True(exportedItemsA.Count == 5);
+ Assert.True(exportedItemsB.Count == 5);
  }
 
  [Fact]
@@ -142,23 +144,27 @@ public void ProcessMetricsAreCapturedWhenTasksOverlap()
 
  Task.WaitAll(tasks.ToArray());
 
- Assert.True(exportedItemsA.Count == 4);
+ Assert.True(exportedItemsA.Count == 5);
  var physicalMemoryMetricA = exportedItemsA.FirstOrDefault(i => i.Name == "process.memory.usage");
  Assert.NotNull(physicalMemoryMetricA);
  var virtualMemoryMetricA = exportedItemsA.FirstOrDefault(i => i.Name == "process.memory.virtual");
  Assert.NotNull(virtualMemoryMetricA);
  var cpuTimeMetricA = exportedItemsA.FirstOrDefault(i => i.Name == "process.cpu.time");
  Assert.NotNull(cpuTimeMetricA);
+ var processorCountMetricA = exportedItemsA.FirstOrDefault(i => i.Name == "process.cpu.count");
+ Assert.NotNull(processorCountMetricA);
  var threadMetricA = exportedItemsA.FirstOrDefault(i => i.Name == "process.threads");
  Assert.NotNull(threadMetricA);
 
- Assert.True(exportedItemsB.Count == 4);
+ Assert.True(exportedItemsB.Count == 5);
  var physicalMemoryMetricB = exportedItemsB.FirstOrDefault(i => i.Name == "process.memory.usage");
  Assert.NotNull(physicalMemoryMetricB);
  var virtualMemoryMetricB = exportedItemsB.FirstOrDefault(i => i.Name == "process.memory.virtual");
  Assert.NotNull(virtualMemoryMetricB);
  var cpuTimeMetricB = exportedItemsB.FirstOrDefault(i => i.Name == "process.cpu.time");
  Assert.NotNull(cpuTimeMetricB);
+ var processorCountMetricB = exportedItemsB.FirstOrDefault(i => i.Name == "process.cpu.count");
+ Assert.NotNull(processorCountMetricB);
  var threadMetricB = exportedItemsB.FirstOrDefault(i => i.Name == "process.threads");
  Assert.NotNull(threadMetricB);
  }