Measure survived once in the constructor to allow jitter to make its allocations for the memory monitor.

Author: timcassell

src/BenchmarkDotNet/Engines/Engine.cs

@@ -82,10 +82,16 @@ internal Engine(
             pilotStage = new EnginePilotStage(this);
             actualStage = new EngineActualStage(this);
 
+            // Necessary for CORE runtimes.
             if (includeSurvivedMemory)
             {
-                // Run the clock once to set static memory (necessary for CORE runtimes).
+                // Measure survived once to allow jit to make its allocations.
+                GcStats.StartMeasuringSurvived(includeSurvivedMemory);
+                // Run the clock once to set static memory.
                 MeasureAction(_ => { }, 0);
+                GcStats.StopMeasuringSurvived(includeSurvivedMemory);
+                // Clear total measured to not pollute actual measurement.
+                GcStats.ClearTotalMeasuredSurvived();
             }
         }
 

src/BenchmarkDotNet/Engines/GcStats.cs

@@ -269,6 +269,11 @@ public static long StopMeasuringSurvived(bool measure)
             return measured;
         }
 
+        public static void ClearTotalMeasuredSurvived()
+        {
+            _totalMeasured = 0;
+        }
+
         private static long GetTotalBytes(bool actual)
         {
             if (!actual || RuntimeInformation.IsMono) // Monitoring is not available in Mono.