lib: faster FreeList

Make FreeList faster by using Reflect.apply and not using
is_reused_symbol, but rather just checking whether any
items are present in the list prior to calling alloc.

PR-URL: #27021
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

benchmark/misc/freelist.js

@@ -9,7 +9,9 @@ const bench = common.createBenchmark(main, {
 });
 
 function main({ n }) {
- const { FreeList } = require('internal/freelist');
+ let FreeList = require('internal/freelist');
+ if (FreeList.FreeList)
+ FreeList = FreeList.FreeList;
  const poolSize = 1000;
  const list = new FreeList('test', poolSize, Object);
  var j;

lib/_http_client.js

@@ -46,7 +46,6 @@ const {
  ERR_UNESCAPED_CHARACTERS
 } = require('internal/errors').codes;
 const { getTimerDuration } = require('internal/timers');
-const is_reused_symbol = require('internal/freelist').symbols.is_reused_symbol;
 const {
  DTRACE_HTTP_CLIENT_REQUEST,
  DTRACE_HTTP_CLIENT_RESPONSE
@@ -631,10 +630,11 @@ function emitFreeNT(socket) {
 }
 
 function tickOnSocket(req, socket) {
+ const isParserReused = parsers.hasItems();
  const parser = parsers.alloc();
  req.socket = socket;
  req.connection = socket;
- parser.reinitialize(HTTPParser.RESPONSE, parser[is_reused_symbol]);
+ parser.reinitialize(HTTPParser.RESPONSE, isParserReused);
  parser.socket = socket;
  parser.outgoing = req;
  req.parser = parser;

lib/_http_common.js

@@ -29,7 +29,7 @@ const { methods, HTTPParser } =
  getOptionValue('--http-parser') === 'legacy' ?
  internalBinding('http_parser') : internalBinding('http_parser_llhttp');
 
-const { FreeList } = require('internal/freelist');
+const FreeList = require('internal/freelist');
 const { ondrain } = require('internal/http');
 const incoming = require('_http_incoming');
 const {

lib/_http_server.js

@@ -41,7 +41,6 @@ const {
  defaultTriggerAsyncIdScope,
  getOrSetAsyncId
 } = require('internal/async_hooks');
-const is_reused_symbol = require('internal/freelist').symbols.is_reused_symbol;
 const { IncomingMessage } = require('_http_incoming');
 const {
  ERR_HTTP_HEADERS_SENT,
@@ -348,8 +347,9 @@ function connectionListenerInternal(server, socket) {
  socket.setTimeout(server.timeout);
  socket.on('timeout', socketOnTimeout);
 
+ const isParserReused = parsers.hasItems();
  const parser = parsers.alloc();
- parser.reinitialize(HTTPParser.REQUEST, parser[is_reused_symbol]);
+ parser.reinitialize(HTTPParser.REQUEST, isParserReused);
  parser.socket = socket;
 
  // We are starting to wait for our headers.

lib/internal/freelist.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const is_reused_symbol = Symbol('isReused');
+const { Reflect } = primordials;
 
 class FreeList {
  constructor(name, max, ctor) {
@@ -10,16 +10,14 @@ class FreeList {
  this.list = [];
  }
 
+ hasItems() {
+ return this.list.length > 0;
+ }
+
  alloc() {
- let item;
- if (this.list.length > 0) {
- item = this.list.pop();
- item[is_reused_symbol] = true;
- } else {
- item = this.ctor.apply(this, arguments);
- item[is_reused_symbol] = false;
- }
- return item;
+ return this.list.length > 0 ?
+ this.list.pop() :
+ Reflect.apply(this.ctor, this, arguments);
  }
 
  free(obj) {
@@ -31,9 +29,4 @@ class FreeList {
  }
 }
 
-module.exports = {
- FreeList,
- symbols: {
- is_reused_symbol
- }
-};
+module.exports = FreeList;

test/parallel/test-freelist.js

@@ -4,7 +4,7 @@
 
 require('../common');
 const assert = require('assert');
-const { FreeList } = require('internal/freelist');
+const FreeList = require('internal/freelist');
 
 assert.strictEqual(typeof FreeList, 'function');
 

test/sequential/test-http-regr-gh-2928.js

@@ -6,7 +6,6 @@
 const common = require('../common');
 const assert = require('assert');
 const httpCommon = require('_http_common');
-const is_reused_symbol = require('internal/freelist').symbols.is_reused_symbol;
 const { HTTPParser } = require('_http_common');
 const net = require('net');
 
@@ -25,14 +24,15 @@ function execAndClose() {
  process.stdout.write('.');
 
  const parser = parsers.pop();
- parser.reinitialize(HTTPParser.RESPONSE, parser[is_reused_symbol]);
+ parser.reinitialize(HTTPParser.RESPONSE, !!parser.reused);
 
  const socket = net.connect(common.PORT);
  socket.on('error', (e) => {
  // If SmartOS and ECONNREFUSED, then retry. See
  // https://github.com/nodejs/node/issues/2663.
  if (common.isSunOS && e.code === 'ECONNREFUSED') {
  parsers.push(parser);
+ parser.reused = true;
  socket.destroy();
  setImmediate(execAndClose);
  return;