use faster timers (nodejs#1908)

* refactor: refreshTimeout

* perf: fast timers

* fixup

* Revert "fixup"

This reverts commit 2fc8eaa7195c931481d902a3f2583f38317td0be8.

* fixup

* fixup

* fixup

* fixup

* fixup

* fixup

* fixup

* fixup

* fixup

* Update lib/timers.js

* Update lib/timers.js

* Update lib/timers.js

lib/client.js

@@ -5,6 +5,7 @@
 const assert = require('assert')
 const net = require('net')
 const util = require('./core/util')
+const timers = require('./timers')
 const Request = require('./core/request')
 const DispatcherBase = require('./dispatcher-base')
 const {
@@ -444,9 +445,9 @@ class Parser {
   setTimeout (value, type) {
     this.timeoutType = type
     if (value !== this.timeoutValue) {
-      clearTimeout(this.timeout)
+      timers.clearTimeout(this.timeout)
       if (value) {
-        this.timeout = setTimeout(onParserTimeout, value, this)
+        this.timeout = timers.setTimeout(onParserTimeout, value, this)
         // istanbul ignore else: only for jest
         if (this.timeout.unref) {
           this.timeout.unref()
@@ -562,7 +563,7 @@ class Parser {
     this.llhttp.llhttp_free(this.ptr)
     this.ptr = null
 
-    clearTimeout(this.timeout)
+    timers.clearTimeout(this.timeout)
     this.timeout = null
     this.timeoutValue = null
     this.timeoutType = null

lib/timers.js

@@ -0,0 +1,89 @@
+'use strict'
+
+let fastNow = Date.now()
+let fastNowTimeout
+
+const fastTimers = []
+
+function onTimeout () {
+  fastNow = Date.now()
+
+  let len = fastTimers.length
+  let idx = 0
+  while (idx < len) {
+    const timer = fastTimers[idx]
+
+    if (timer.expires && fastNow >= timer.expires) {
+      timer.expires = 0
+      timer.callback(timer.opaque)
+    }
+
+    if (timer.expires === 0) {
+      timer.active = false
+      if (idx !== len - 1) {
+        fastTimers[idx] = fastTimers.pop()
+      } else {
+        fastTimers.pop()
+      }
+      len -= 1
+    } else {
+      idx += 1
+    }
+  }
+
+  if (fastTimers.length > 0) {
+    refreshTimeout()
+  }
+}
+
+function refreshTimeout () {
+  if (fastNowTimeout && fastNowTimeout.refresh) {
+    fastNowTimeout.refresh()
+  } else {
+    clearTimeout(fastNowTimeout)
+    fastNowTimeout = setTimeout(onTimeout, 1e3)
+    if (fastNowTimeout.unref) {
+      fastNowTimeout.unref()
+    }
+  }
+}
+
+class Timeout {
+  constructor (callback, delay, opaque) {
+    this.callback = callback
+    this.delay = delay
+    this.opaque = opaque
+    this.expires = 0
+    this.active = false
+
+    this.refresh()
+  }
+
+  refresh () {
+    if (!this.active) {
+      this.active = true
+      fastTimers.push(this)
+      if (!fastNowTimeout || fastTimers.length === 1) {
+        refreshTimeout()
+        fastNow = Date.now()
+      }
+    }
+
+    this.expires = fastNow + this.delay
+  }
+
+  clear () {
+    this.expires = 0
+  }
+}
+
+module.exports = {
+  setTimeout (callback, delay, opaque) {
+    return new Timeout(callback, delay, opaque)
+  },
+  clearTimeout (timeout) {
+    if (timeout && timeout.clear) {
+      timeout.clear()
+    }
+  }
+}

test/client-keep-alive.js

@@ -2,6 +2,7 @@
 
 const { test } = require('tap')
 const { Client } = require('..')
+const timers = require('../lib/timers')
 const { kConnect } = require('../lib/core/symbols')
 const { createServer } = require('net')
 const http = require('http')
@@ -47,6 +48,12 @@ test('keep-alive header 0', (t) => {
   const clock = FakeTimers.install()
   t.teardown(clock.uninstall.bind(clock))
 
+  const orgTimers = { ...timers }
+  Object.assign(timers, { setTimeout, clearTimeout })
+  t.teardown(() => {
+    Object.assign(timers, orgTimers)
+  })
+
   const server = createServer((socket) => {
     socket.write('HTTP/1.1 200 OK\r\n')
     socket.write('Content-Length: 0\r\n')

test/client-reconnect.js

@@ -4,6 +4,7 @@ const { test } = require('tap')
 const { Client } = require('..')
 const { createServer } = require('http')
 const FakeTimers = require('@sinonjs/fake-timers')
+const timers = require('../lib/timers')
 
 test('multiple reconnect', (t) => {
   t.plan(5)
@@ -12,6 +13,12 @@ test('multiple reconnect', (t) => {
   const clock = FakeTimers.install()
   t.teardown(clock.uninstall.bind(clock))
 
+  const orgTimers = { ...timers }
+  Object.assign(timers, { setTimeout, clearTimeout })
+  t.teardown(() => {
+    Object.assign(timers, orgTimers)
+  })
+
   const server = createServer((req, res) => {
     n === 0 ? res.destroy() : res.end('ok')
   })

test/client-timeout.js

@@ -5,6 +5,7 @@ const { Client, errors } = require('..')
 const { createServer } = require('http')
 const { Readable } = require('stream')
 const FakeTimers = require('@sinonjs/fake-timers')
+const timers = require('../lib/timers')
 
 test('refresh timeout on pause', (t) => {
   t.plan(1)
@@ -51,6 +52,12 @@ test('start headers timeout after request body', (t) => {
   const clock = FakeTimers.install()
   t.teardown(clock.uninstall.bind(clock))
 
+  const orgTimers = { ...timers }
+  Object.assign(timers, { setTimeout, clearTimeout })
+  t.teardown(() => {
+    Object.assign(timers, orgTimers)
+  })
+
   const server = createServer((req, res) => {
   })
   t.teardown(server.close.bind(server))
@@ -101,6 +108,12 @@ test('start headers timeout after async iterator request body', (t) => {
   const clock = FakeTimers.install()
   t.teardown(clock.uninstall.bind(clock))
 
+  const orgTimers = { ...timers }
+  Object.assign(timers, { setTimeout, clearTimeout })
+  t.teardown(() => {
+    Object.assign(timers, orgTimers)
+  })
+
   const server = createServer((req, res) => {
   })
   t.teardown(server.close.bind(server))
@@ -167,7 +180,7 @@ test('parser resume with no body timeout', (t) => {
       onConnect () {
       },
       onHeaders (statusCode, headers, resume) {
-        setTimeout(resume, 100)
+        setTimeout(resume, 2000)
         return false
       },
       onData () {

test/fetch/fetch-timeouts.js

@@ -3,6 +3,7 @@
 const { test } = require('tap')
 
 const { fetch, Agent } = require('../..')
+const timers = require('../../lib/timers')
 const { createServer } = require('http')
 const FakeTimers = require('@sinonjs/fake-timers')
 
@@ -16,6 +17,12 @@ test('Fetch very long request, timeout overridden so no error', (t) => {
   const clock = FakeTimers.install()
   t.teardown(clock.uninstall.bind(clock))
 
+  const orgTimers = { ...timers }
+  Object.assign(timers, { setTimeout, clearTimeout })
+  t.teardown(() => {
+    Object.assign(timers, orgTimers)
+  })
+
   const server = createServer((req, res) => {
     setTimeout(() => {
       res.end('hello')