[Instrumentation.Process] Add CPU metrics (#678)

open-telemetry · Oct 11, 2022 · cbed25e · cbed25e
1 parent b9e3d88
commit cbed25e
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Showing 2 changed files with 68 additions and 1 deletion.
diff --git a/src/OpenTelemetry.Instrumentation.Process/ProcessMetrics.cs b/src/OpenTelemetry.Instrumentation.Process/ProcessMetrics.cs
@@ -14,6 +14,7 @@
 // limitations under the License.
 // </copyright>
 
+using System.Collections.Generic;
 using System.Diagnostics.Metrics;
 using System.Reflection;
 using Diagnostics = System.Diagnostics;
@@ -28,6 +29,8 @@ internal sealed class ProcessMetrics
     private readonly Diagnostics.Process currentProcess = Diagnostics.Process.GetCurrentProcess();
     private double? memoryUsage;
     private double? virtualMemoryUsage;
+    private double? userProcessorTime;
+    private double? privilegedProcessorTime;
 
     public ProcessMetrics(ProcessInstrumentationOptions options)
     {
@@ -64,12 +67,37 @@ public ProcessMetrics(ProcessInstrumentationOptions options)
             },
             unit: "By",
             description: "The amount of virtual memory allocated for this process that cannot be shared with other processes.");
+
+        this.MeterInstance.CreateObservableCounter(
+            "process.cpu.time",
+            () =>
+            {
+                if (!this.userProcessorTime.HasValue || !this.privilegedProcessorTime.HasValue)
+                {
+                    this.Snapshot();
+                }
+
+                var userProcessorTimeValue = this.userProcessorTime.Value;
+                var privilegedProcessorTimeValue = this.privilegedProcessorTime.Value;
+                this.userProcessorTime = null;
+                this.privilegedProcessorTime = null;
+
+                return new[]
+                {
+                    new Measurement<double>(userProcessorTimeValue, new KeyValuePair<string, object?>("state", "user")),
+                    new Measurement<double>(privilegedProcessorTimeValue, new KeyValuePair<string, object?>("state", "system")),
+                };
+            },
+            unit: "s",
+            description: "Total CPU seconds broken down by different states.");
     }
 
     private void Snapshot()
     {
         this.currentProcess.Refresh();
         this.memoryUsage = this.currentProcess.WorkingSet64;
         this.virtualMemoryUsage = this.currentProcess.PrivateMemorySize64;
+        this.userProcessorTime = this.currentProcess.UserProcessorTime.TotalSeconds;
+        this.privilegedProcessorTime = this.currentProcess.PrivilegedProcessorTime.TotalSeconds;
     }
 }
diff --git a/test/OpenTelemetry.Instrumentation.Process.Tests/ProcessMetricsTests.cs b/test/OpenTelemetry.Instrumentation.Process.Tests/ProcessMetricsTests.cs
@@ -37,11 +37,50 @@ public void ProcessMetricsAreCaptured()
 
         meterProvider.ForceFlush(MaxTimeToAllowForFlush);
 
-        Assert.True(exportedItems.Count == 2);
+        Assert.True(exportedItems.Count == 3);
         var physicalMemoryMetric = exportedItems.FirstOrDefault(i => i.Name == "process.memory.usage");
         Assert.NotNull(physicalMemoryMetric);
         var virtualMemoryMetric = exportedItems.FirstOrDefault(i => i.Name == "process.memory.virtual");
         Assert.NotNull(virtualMemoryMetric);
+        var cpuTimeMetric = exportedItems.FirstOrDefault(i => i.Name == "process.cpu.time");
+        Assert.NotNull(cpuTimeMetric);
+    }
+
+    [Fact]
+    public void CpuTimeMetricsAreCaptured()
+    {
+        var exportedItems = new List<Metric>();
+        using var meterProvider = Sdk.CreateMeterProviderBuilder()
+            .AddProcessInstrumentation()
+            .AddInMemoryExporter(exportedItems)
+            .Build();
+
+        meterProvider.ForceFlush(MaxTimeToAllowForFlush);
+
+        var cpuTimeMetric = exportedItems.FirstOrDefault(i => i.Name == "process.cpu.time");
+        Assert.NotNull(cpuTimeMetric);
+
+        var userTimeCaptured = false;
+        var systemTimeCaptured = false;
+
+        var points = cpuTimeMetric.GetMetricPoints().GetEnumerator();
+        while (points.MoveNext() && (!userTimeCaptured || !systemTimeCaptured))
+        {
+            foreach (var tag in points.Current.Tags)
+            {
+                if (tag.Key == "state" && tag.Value.ToString() == "user")
+                {
+                    userTimeCaptured = true;
+                }
+                else if (tag.Key == "state" && tag.Value.ToString() == "system")
+                {
+                    systemTimeCaptured = true;
+                }
+            }
+        }
+
+        Assert.True(userTimeCaptured);
+        Assert.True(systemTimeCaptured);
     }
 
     [Fact]