Buffer.concat

buff_concat_benchmark.js

var Benchmark = require('benchmark');
var suite = new Benchmark.Suite();

var buff = new Buffer(10);
var buff100 = new Buffer(100);
var buff1000 = new Buffer(1000);
var buff8000 = new Buffer(8000);

var make_buffers = function (buf, length) {
  var list = [];
  for (var i = 0; i < length; i++) {
    list.push(buf);
  }
  return list;
};

var new_concat = function(list, length) {
  if (!Array.isArray(list))
    throw new TypeError('list argument must be an Array of Buffers.');

  if (list.length === 0)
    return new Buffer(0);
  else if (list.length === 1)
    return list[0];

  if (length === undefined) {
    length = 0;
    for (var i = 0; i < list.length; i++)
      length += list[i].length;
  } else {
    length = length >>> 0;
  }

  var buffer = new Buffer(length);
  var pos = 0;
  for (var i = 0; i < list.length; i++) {
    var buf = list[i];
    buf.copy(buffer, pos);
    pos += buf.length;
  }

  return buffer;
};

var old_concat = function(list, length) {
  if (!Array.isArray(list))
    throw new TypeError('list argument must be an Array of Buffers.');

  if (length === undefined) {
    length = 0;
    for (var i = 0; i < list.length; i++)
      length += list[i].length;
  } else {
    length = length >>> 0;
  }

  if (list.length === 0)
    return new Buffer(0);
  else if (list.length === 1)
    return list[0];

  var buffer = new Buffer(length);
  var pos = 0;
  for (var i = 0; i < list.length; i++) {
    var buf = list[i];
    buf.copy(buffer, pos);
    pos += buf.length;
  }

  return buffer;
};

var empty_list = make_buffers(new Buffer(0), 0);
var buff_1 = make_buffers(buff, 1);
var buff_2 = make_buffers(buff, 2);
var buff_10 = make_buffers(buff, 10);
var buff_100 = make_buffers(buff, 100);
var buff100_1 = make_buffers(buff100, 1);
var buff100_2 = make_buffers(buff100, 2);
var buff100_10 = make_buffers(buff100, 10);
var buff100_100 = make_buffers(buff100, 100);
var buff1000_1 = make_buffers(buff1000, 1);
var buff1000_2 = make_buffers(buff1000, 2);
var buff1000_10 = make_buffers(buff1000, 10);
var buff1000_100 = make_buffers(buff1000, 100);

suite
.add("new length 0", function () {
  new_concat(empty_list);
})
.add('new length 1', function () {
  new_concat(buff_1);
})
.add("new length 2", function () {
  new_concat(buff_2);
})
.add("new length 10", function () {
  new_concat(buff_10);
})
.add("new length 100", function () {
  new_concat(buff_100);
})
.add("old length 0", function () {
  old_concat(empty_list);
})
.add('old length 1', function () {
  old_concat(buff_1);
})
.add("old length 2", function () {
  old_concat(buff_2);
})
.add("old length 10", function () {
  old_concat(buff_10);
})
.add("old length 100", function () {
  old_concat(buff_100);
})
.add("buff100 new length 0", function () {
  new_concat(empty_list);
})
.add('buff100 new length 1', function () {
  new_concat(buff100_1);
})
.add("buff100 new length 2", function () {
  new_concat(buff100_2);
})
.add("buff100 new length 10", function () {
  new_concat(buff100_10);
})
.add("buff100 new length 100", function () {
  new_concat(buff100_100);
})
.add("buff100 old length 0", function () {
  old_concat(empty_list);
})
.add('buff100 old length 1', function () {
  old_concat(buff100_1);
})
.add("buff100 old length 2", function () {
  old_concat(buff100_2);
})
.add("buff100 old length 10", function () {
  old_concat(buff100_10);
})
.add("buff100 old length 100", function () {
  old_concat(buff100_100);
})
.add("buff1000 new length 0", function () {
  new_concat(empty_list);
})
.add('buff1000 new length 1', function () {
  new_concat(buff1000_1);
})
.add("buff1000 new length 2", function () {
  new_concat(buff1000_2);
})
.add("buff1000 new length 10", function () {
  new_concat(buff1000_10);
})
.add("buff1000 new length 100", function () {
  new_concat(buff1000_100);
})
.add("buff1000 old length 0", function () {
  old_concat(empty_list);
})
.add('buff1000 old length 1', function () {
  old_concat(buff1000_1);
})
.add("buff1000 old length 2", function () {
  old_concat(buff1000_2);
})
.add("buff1000 old length 10", function () {
  old_concat(buff1000_10);
})
.add("buff1000 old length 100", function () {
  old_concat(buff1000_100);
})
// add listeners
.on('cycle', function (event) {
  console.log(String(event.target));
})
.on('complete', function () {
  console.log('Fastest is ' + this.filter('fastest').pluck('name'));
})
.run({ async: false });

result.md

new length 0 x 1,034,624 ops/sec ±10.05% (43 runs sampled)
new length 1 x 45,085,806 ops/sec ±1.91% (84 runs sampled)
new length 2 x 2,051,267 ops/sec ±3.48% (83 runs sampled)
new length 10 x 821,860 ops/sec ±2.83% (81 runs sampled)
new length 100 x 110,519 ops/sec ±3.61% (82 runs sampled)
old length 0 x 1,127,066 ops/sec ±12.44% (48 runs sampled)
old length 1 x 33,351,696 ops/sec ±3.21% (83 runs sampled)
old length 2 x 1,862,283 ops/sec ±2.60% (80 runs sampled)
old length 10 x 757,834 ops/sec ±2.87% (79 runs sampled)
old length 100 x 101,986 ops/sec ±4.56% (78 runs sampled)
buff100 new length 0 x 1,023,448 ops/sec ±13.61% (49 runs sampled)
buff100 new length 1 x 30,414,166 ops/sec ±2.36% (78 runs sampled)
buff100 new length 2 x 1,567,395 ops/sec ±2.90% (77 runs sampled)
buff100 new length 10 x 480,774 ops/sec ±8.99% (66 runs sampled)
buff100 new length 100 x 62,559 ops/sec ±9.34% (67 runs sampled)
buff100 old length 0 x 1,053,923 ops/sec ±12.64% (46 runs sampled)
buff100 old length 1 x 26,407,231 ops/sec ±2.50% (81 runs sampled)
buff100 old length 2 x 1,507,457 ops/sec ±3.31% (78 runs sampled)
buff100 old length 10 x 476,436 ops/sec ±9.79% (63 runs sampled)
buff100 old length 100 x 62,212 ops/sec ±9.47% (66 runs sampled)
buff1000 new length 0 x 1,080,568 ops/sec ±13.01% (48 runs sampled)
buff1000 new length 1 x 29,699,749 ops/sec ±2.22% (77 runs sampled)
buff1000 new length 2 x 455,777 ops/sec ±9.82% (55 runs sampled)
buff1000 new length 10 x 116,589 ops/sec ±8.86% (56 runs sampled)
buff1000 new length 100 x 15,547 ops/sec ±4.71% (52 runs sampled)
buff1000 old length 0 x 1,102,854 ops/sec ±12.80% (49 runs sampled)
buff1000 old length 1 x 29,228,265 ops/sec ±2.07% (85 runs sampled)
buff1000 old length 2 x 455,276 ops/sec ±9.88% (53 runs sampled)
buff1000 old length 10 x 115,662 ops/sec ±8.60% (55 runs sampled)
buff1000 old length 100 x 15,664 ops/sec ±1.99% (44 runs sampled)
Fastest is new length 1