Question

我想确定javascript中小树节点的最佳结构。每个节点都有键，值和对父节点和子节点的引用（如果存在）。所以我编写了测试节点创建性能的基准：

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

suite
.add('Object node creation', function() {
    var parent = {
        key:    'some_key',
        value:  1234123412,
        parent: null,
        left:   null,
        right:  null
    };

    var left = {
        key: 'left child',
        value: 'asdfoasjdfpasdjf',
        parent: null,
        left:   null,
        right:  null
    };

    var right = {
        key:   'right child',
        value: 'qwerqwerqwerqwwq',
        parent: null,
        left:   null,
        right:  null
    };

    parent.left  = left;
    parent.right = right;
    left.parent  = parent;
    right.parent = parent;
})
.add('Array node creation', function() {
    var parent = ['some_key',    1234123412,         null, null, null];
    var left   = ['left_child',  'asdfoasjdfpasdjf', null, null, null];
    var right  = ['right_child', 'qwerqwerqwerqwwq', null, null, null];

    parent[3] = left;
    parent[4] = right;
    left[2]   = parent;
    right[2]  = parent;
})
.on('complete', function() {
    console.log(this[0].toString());
    console.log(this[1].toString());

    console.log('Fastest is ' + this.filter('fastest').pluck('name'));
})
.run();

所以我运行测试：

node benchmark.js

并得到以下结果：

Object node creation x 30,613,857 ops/sec ±3.11% (82 runs sampled)
Array node creation x 15,133,139 ops/sec ±1.12% (94 runs sampled)
Fastest is Object node creation

没关系。

然后我用--debug-brk运行基准：

 node --debug-brk benchmark.js

并获得以下结果：

Object node creation x 4,842,367 ops/sec ±2.81% (90 runs sampled)
Array node creation x 10,906,219 ops/sec ±2.36% (90 runs sampled)
Fastest is Array node creation

如您所见：对象创建的性能急剧下降。也许有人可以解释我为什么会这样以及发生了什么。

在--debug-brk标志下的Strange Object vs. Array基准测试结果

0 个答案: