1 files changed, 1 insertions, 0 deletions
diff --git a/lib/perf_hooks.js b/lib/perf_hooks.js
index 1bf635790e..12909b047c 100644
--- a/lib/perf_hooks.js
+++ b/lib/perf_hooks.js
@@ -354,6 +354,7 @@ class PerformanceObserver extends AsyncResource {
     for (var n = 0; n < entryTypes.length; n++) {
       const entryType = entryTypes[n];
       const list = getObserversList(entryType);
+      if (this[kTypes][entryType]) continue;
       const item = { obs: this };
       this[kTypes][entryType] = item;
       L.append(list, item);