From 47e4fb952baf324d3d3ac78ba0685447a575e261 Mon Sep 17 00:00:00 2001
From: James M Snell <jasnell@gmail.com>
Date: Wed, 3 Jun 2020 18:13:01 -0700
Subject: [PATCH 1/2] events: lazy load perf_hooks for EventTarget

---
 lib/internal/event_target.js | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/lib/internal/event_target.js b/lib/internal/event_target.js
index 8641129b132914..3df88cedf58a3d 100644
--- a/lib/internal/event_target.js
+++ b/lib/internal/event_target.js
@@ -19,7 +19,6 @@ const {
   }
 } = require('internal/errors');
 
-const perf_hooks = require('perf_hooks');
 const { customInspectSymbol } = require('internal/util');
 const { inspect } = require('util');
 
@@ -30,11 +29,19 @@ const kTarget = Symbol('kTarget');
 const kNewListener = Symbol('kNewListener');
 const kRemoveListener = Symbol('kRemoveListener');
 
+// Lazy load perf_hooks to avoid the additional overhead on startup
+let perf_hooks;
+function lazyNow() {
+  if (perf_hooks === undefined)
+    perf_hooks = require('perf_hooks');
+  return perf_hooks.performance.now();
+}
+
 class Event {
   #type = undefined;
   #defaultPrevented = false;
   #cancelable = false;
-  #timestamp = perf_hooks.performance.now();
+  #timestamp = lazyNow();
 
   // None of these are currently used in the Node.js implementation
   // of EventTarget because there is no concept of bubbling or

From a19d755b13f4837bb98bb12469d1757479715d5e Mon Sep 17 00:00:00 2001
From: James M Snell <jasnell@gmail.com>
Date: Mon, 8 Jun 2020 09:26:40 -0700
Subject: [PATCH 2/2] fixup! events: lazy load perf_hooks for EventTarget

---
 test/parallel/test-bootstrap-modules.js | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/test/parallel/test-bootstrap-modules.js b/test/parallel/test-bootstrap-modules.js
index b2506499e7d1c7..86a91062ce7143 100644
--- a/test/parallel/test-bootstrap-modules.js
+++ b/test/parallel/test-bootstrap-modules.js
@@ -20,7 +20,6 @@ const expectedModules = new Set([
   'Internal Binding module_wrap',
   'Internal Binding native_module',
   'Internal Binding options',
-  'Internal Binding performance',
   'Internal Binding process_methods',
   'Internal Binding report',
   'Internal Binding string_decoder',
@@ -31,7 +30,6 @@ const expectedModules = new Set([
   'Internal Binding types',
   'Internal Binding url',
   'Internal Binding util',
-  'NativeModule async_hooks',
   'NativeModule buffer',
   'NativeModule events',
   'NativeModule fs',
@@ -49,7 +47,6 @@ const expectedModules = new Set([
   'NativeModule internal/fixed_queue',
   'NativeModule internal/fs/dir',
   'NativeModule internal/fs/utils',
-  'NativeModule internal/histogram',
   'NativeModule internal/idna',
   'NativeModule internal/linkedlist',
   'NativeModule internal/modules/run_main',
@@ -86,7 +83,6 @@ const expectedModules = new Set([
   'NativeModule internal/validators',
   'NativeModule internal/vm/module',
   'NativeModule path',
-  'NativeModule perf_hooks',
   'NativeModule timers',
   'NativeModule url',
   'NativeModule util',