--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.jfr/share/classes/jdk/jfr/internal/OldObjectSample.java	Mon Jun 25 02:07:42 2018 +0200
@@ -0,0 +1,73 @@
+package jdk.jfr.internal;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import jdk.jfr.Enabled;
+import jdk.jfr.RecordingState;
+import jdk.jfr.internal.settings.CutoffSetting;
+import jdk.jfr.internal.test.WhiteBox;
+
+// The Old Object event could have been implemented as a periodic event, but
+// due to chunk rotations and how settings are calculated when multiple recordings
+// are running at the same time, it would lead to unacceptable overhead.
+//
+// Instead, the event is only emitted before a recording stops and
+// if that recording has the event enabled.
+//
+// This requires special handling and the purpose of this class is to provide that
+//
+public final class OldObjectSample {
+
+    private static final String EVENT_NAME = Type.EVENT_NAME_PREFIX + "OldObjectSample";
+    private static final String OLD_OBJECT_CUTOFF = EVENT_NAME + "#" + Cutoff.NAME;
+    private static final String OLD_OBJECT_ENABLED = EVENT_NAME + "#" + Enabled.NAME;
+
+    // Emit if old object is enabled in recoding with cutoff for that recording
+    public static void emit(PlatformRecording recording) {
+        if (isEnabled(recording)) {
+            long nanos = CutoffSetting.parseValueSafe(recording.getSettings().get(OLD_OBJECT_CUTOFF));
+            long ticks = Utils.nanosToTicks(nanos);
+            JVM.getJVM().emitOldObjectSamples(ticks, WhiteBox.getWriteAllObjectSamples());
+        }
+    }
+
+    // Emit if old object is enabled for at least one recording, and use the largest
+    // cutoff for an enabled recoding
+    public static void emit(List<PlatformRecording> recordings, Boolean pathToGcRoots) {
+        boolean enabled = false;
+        long cutoffNanos = Boolean.TRUE.equals(pathToGcRoots) ? Long.MAX_VALUE : 0L;
+        for (PlatformRecording r : recordings) {
+            if (r.getState() == RecordingState.RUNNING) {
+                if (isEnabled(r)) {
+                    enabled = true;
+                    long c = CutoffSetting.parseValueSafe(r.getSettings().get(OLD_OBJECT_CUTOFF));
+                    cutoffNanos = Math.max(c, cutoffNanos);
+                }
+            }
+        }
+        if (enabled) {
+            long ticks = Utils.nanosToTicks(cutoffNanos);
+            JVM.getJVM().emitOldObjectSamples(ticks, WhiteBox.getWriteAllObjectSamples());
+        }
+    }
+
+    public static void updateSettingPathToGcRoots(Map<String, String> s, Boolean pathToGcRoots) {
+        if (pathToGcRoots != null) {
+            s.put(OLD_OBJECT_CUTOFF, pathToGcRoots ? "infinity" : "0 ns");
+        }
+    }
+
+    public static Map<String, String> createSettingsForSnapshot(PlatformRecording recording, Boolean pathToGcRoots) {
+        Map<String, String> settings = new HashMap<>(recording.getSettings());
+        updateSettingPathToGcRoots(settings, pathToGcRoots);
+        return settings;
+    }
+
+    private static boolean isEnabled(PlatformRecording r) {
+        Map<String, String> settings = r.getSettings();
+        String s = settings.get(OLD_OBJECT_ENABLED);
+        return "true".equals(s);
+    }
+}