Update a few metrics to be in sync of doc updates for gc.heap, `gc.…

…fragmentation.ratio`, `time.in.jit`, `process.cpu.count` and `assembly.count` (#430)

src/OpenTelemetry.Instrumentation.Runtime/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+* Update a few metrics to be in sync of doc updates for `gc.heap`,
+  `gc.fragmentation.ratio`, `time.in.jit`, `process.cpu.count` and `assembly.count`
+  ([#430](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/430))
+
 ## 0.2.0-alpha.1
 
 * Updated OTel SDK package version to 1.3.0

src/OpenTelemetry.Instrumentation.Runtime/RuntimeMetrics.cs

@@ -49,17 +49,16 @@ public RuntimeMetrics(RuntimeMetricsOptions options)
 
             if (options.IsGcEnabled)
             {
-                // TODO: Almost all the ObservableGauge should be ObservableUpDownCounter (except for CPU utilization and fragmentation.ratio.
+                // TODO: Almost all the ObservableGauge should be ObservableUpDownCounter (except for CPU utilization).
                 // Replace them once ObservableUpDownCounter is available.
-                this.meter.CreateObservableGauge($"{metricPrefix}gc.heap", () => GC.GetTotalMemory(false), "By", "GC Heap Size.");
                 this.meter.CreateObservableGauge($"{metricPrefix}gc.count", () => GetGarbageCollectionCounts(), description: "GC Count for all generations.");
 
 #if NETCOREAPP3_1_OR_GREATER
                 this.meter.CreateObservableCounter($"{metricPrefix}gc.allocated.bytes", () => GC.GetTotalAllocatedBytes(), "By", "Allocation Rate.");
-                this.meter.CreateObservableGauge($"{metricPrefix}gc.fragmentation.ratio", GetFragmentation, description: "GC Fragmentation.");
 #endif
 
 #if NET6_0_OR_GREATER
+                this.meter.CreateObservableGauge($"{metricPrefix}gc.fragmentation.size", GetFragmentationSizes, description: "GC fragmentation.");
                 this.meter.CreateObservableGauge($"{metricPrefix}gc.committed", () => GC.GetGCMemoryInfo().TotalCommittedBytes, "By", description: "GC Committed Bytes.");
                 this.meter.CreateObservableGauge($"{metricPrefix}gc.heapsize", () => GetGarbageCollectionHeapSizes(), "By", "Heap size for all generations.");
 #endif
@@ -70,7 +69,7 @@ public RuntimeMetrics(RuntimeMetricsOptions options)
             {
                 this.meter.CreateObservableCounter($"{metricPrefix}il.bytes.jitted", () => System.Runtime.JitInfo.GetCompiledILBytes(), "By", description: "IL Bytes Jitted.");
                 this.meter.CreateObservableCounter($"{metricPrefix}methods.jitted.count", () => System.Runtime.JitInfo.GetCompiledMethodCount(), description: "Number of Methods Jitted.");
-                this.meter.CreateObservableGauge($"{metricPrefix}time.in.jit", () => System.Runtime.JitInfo.GetCompilationTime().Ticks * NanosecondsPerTick, "ns", description: "Time spent in JIT.");
+                this.meter.CreateObservableCounter($"{metricPrefix}time.in.jit", () => System.Runtime.JitInfo.GetCompilationTime().Ticks * NanosecondsPerTick, "ns", description: "Time spent in JIT.");
             }
 #endif
 
@@ -88,16 +87,13 @@ public RuntimeMetrics(RuntimeMetricsOptions options)
             if (options.IsProcessEnabled)
             {
                 this.meter.CreateObservableCounter("process.cpu.time", GetProcessorTimes, "s", "Processor time of this process.");
-
-                // Not yet official: https://github.com/open-telemetry/opentelemetry-specification/pull/2392
-                this.meter.CreateObservableGauge("process.cpu.count", () => (long)Environment.ProcessorCount, description: "The number of available logical CPUs.");
                 this.meter.CreateObservableGauge("process.memory.usage", () => Process.GetCurrentProcess().WorkingSet64, "By", "The amount of physical memory in use.");
                 this.meter.CreateObservableGauge("process.memory.virtual", () => Process.GetCurrentProcess().VirtualMemorySize64, "By", "The amount of committed virtual memory.");
             }
 
             if (options.IsAssembliesEnabled)
             {
-                this.meter.CreateObservableCounter($"{metricPrefix}assembly.count", () => (long)AppDomain.CurrentDomain.GetAssemblies().Length, description: "Number of Assemblies Loaded.");
+                this.meter.CreateObservableGauge($"{metricPrefix}assembly.count", () => (long)AppDomain.CurrentDomain.GetAssemblies().Length, description: "Number of Assemblies Loaded.");
             }
         }
 
@@ -115,15 +111,20 @@ private static IEnumerable<Measurement<long>> GetGarbageCollectionCounts()
             }
         }
 
-#if NETCOREAPP3_1_OR_GREATER
-        private static double GetFragmentation()
+#if NET6_0_OR_GREATER
+        private static IEnumerable<Measurement<long>> GetFragmentationSizes()
         {
-            var gcInfo = GC.GetGCMemoryInfo();
-            return gcInfo.HeapSizeBytes != 0 ? gcInfo.FragmentedBytes * 1.0d / gcInfo.HeapSizeBytes : 0;
+            var generationInfo = GC.GetGCMemoryInfo().GenerationInfo;
+            Measurement<long>[] measurements = new Measurement<long>[generationInfo.Length];
+            int maxSupportedLength = Math.Min(generationInfo.Length, GenNames.Length);
+            for (int i = 0; i < maxSupportedLength; ++i)
+            {
+                measurements[i] = new(generationInfo[i].FragmentationAfterBytes, new KeyValuePair<string, object>("gen", GenNames[i]));
+            }
+
+            return measurements;
         }
-#endif
 
-#if NET6_0_OR_GREATER
         private static IEnumerable<Measurement<long>> GetGarbageCollectionHeapSizes()
         {
             var generationInfo = GC.GetGCMemoryInfo().GenerationInfo;

test/OpenTelemetry.Instrumentation.Runtime.Tests/RuntimeMetricsTests.cs

@@ -75,15 +75,12 @@ public void ProcessMetricsAreCaptured()
 
             meterProvider.ForceFlush(MaxTimeToAllowForFlush);
 
-            Assert.Equal(4, exportedItems.Count);
+            Assert.Equal(3, exportedItems.Count);
 
             var cpuTimeMetric = exportedItems.First(i => i.Name == "process.cpu.time");
             var sumReceived = GetDoubleSum(cpuTimeMetric);
             Assert.True(sumReceived > 0);
 
-            var cpuCountMetric = exportedItems.First(i => i.Name == "process.cpu.count");
-            Assert.Equal(Environment.ProcessorCount, (int)GetLongSum(cpuCountMetric));
-
             var memoryMetric = exportedItems.First(i => i.Name == "process.memory.usage");
             Assert.True(GetLongSum(memoryMetric) > 0);