async_hooks: lazy loading for startup performance

PR-URL: #20567
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>

Author: BridgeAR

lib/internal/inspector_async_hook.js

@@ -1,49 +1,56 @@
 'use strict';
 
-const{ createHook }=require('async_hooks');
 constinspector=process.binding('inspector');
-constconfig=process.binding('config');
 
 if(!inspector||!inspector.asyncTaskScheduled){
 exports.setup=function(){};
 return;
 }
 
-consthook=createHook({
-init(asyncId,type,triggerAsyncId,resource){
+lethook;
+letconfig;
+
+functionlazyHookCreation(){
+const{ createHook }=require('async_hooks');
+config=process.binding('config');
+
+hook=createHook({
+init(asyncId,type,triggerAsyncId,resource){
 // It's difficult to tell which tasks will be recurring and which won't,
 // therefore we mark all tasks as recurring. Based on the discussion
 // in https://github.com/nodejs/node/pull/13870#discussion_r124515293,
 // this should be fine as long as we call asyncTaskCanceled() too.
-constrecurring=true;
-if(type==='PROMISE')
-this.promiseIds.add(asyncId);
-else
-inspector.asyncTaskScheduled(type,asyncId,recurring);
-},
+constrecurring=true;
+if(type==='PROMISE')
+this.promiseIds.add(asyncId);
+else
+inspector.asyncTaskScheduled(type,asyncId,recurring);
+},
 
-before(asyncId){
-if(this.promiseIds.has(asyncId))
-return;
-inspector.asyncTaskStarted(asyncId);
-},
+before(asyncId){
+if(this.promiseIds.has(asyncId))
+return;
+inspector.asyncTaskStarted(asyncId);
+},
 
-after(asyncId){
-if(this.promiseIds.has(asyncId))
-return;
-inspector.asyncTaskFinished(asyncId);
-},
+after(asyncId){
+if(this.promiseIds.has(asyncId))
+return;
+inspector.asyncTaskFinished(asyncId);
+},
 
-destroy(asyncId){
-if(this.promiseIds.has(asyncId))
-returnthis.promiseIds.delete(asyncId);
-inspector.asyncTaskCanceled(asyncId);
-},
-});
+destroy(asyncId){
+if(this.promiseIds.has(asyncId))
+returnthis.promiseIds.delete(asyncId);
+inspector.asyncTaskCanceled(asyncId);
+},
+});
 
-hook.promiseIds=newSet();
+hook.promiseIds=newSet();
+}
 
 functionenable(){
+if(hook===undefined)lazyHookCreation();
 if(config.bits<64){
 // V8 Inspector stores task ids as (void*) pointers.
 // async_hooks store ids as 64bit numbers.
@@ -61,6 +68,7 @@ function enable() {
 }
 
 functiondisable(){
+if(hook===undefined)lazyHookCreation();
 hook.disable();
 }