Perf optimization for function hooks in Node.JS

perf.js

var microtime = require('microtime'),
    i,
    t,
    obj,
    max = 10000000;

function run1(obj) {
    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        if (obj.foo) obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'conditional to true');
}


function run2(obj) {
    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        obj.foo && obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'true && function()');
}


function run3(obj) {
    obj.foo = null; // seeting value to falsy

    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        if (obj.foo) obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'conditional to false setting value to null');
}


function run4(obj) {
    obj.foo = null; // seeting value to falsy

    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        obj.foo && obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'false && function()');
}


function run5(obj) {
    delete obj.foo; // deleting member

    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        if (obj.foo) obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'conditional to false by deleting member');
}


function run6(obj) {
    delete obj.foo; // deleting member

    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        obj.foo && obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'undefined && function() by deleting member');
}


function run7(obj) {
    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        if (obj.foo) obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'conditional to undefined');
}


function run8(obj) {
    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        obj.foo && obj.foo();
        obj.run();
    }
    console.log(microtime.now() - t, 'undefined && function()');
}


function run9(obj) {
    // conditional to true
    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        obj.run();
    }
    console.log(microtime.now() - t, 'function without replace');
}


function run10(obj) {
    // wrapping original function
    obj._run = obj.run;
    obj.run = function () {
        this.foo();
        this._run();
    };

    t = microtime.now();
    for (i = 0; i < max; i += 1) {
        obj.run();
    }
    console.log(microtime.now() - t, 'function with replace');
}


run9({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run10({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run2({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run4({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});

console.log('--------------');
run1({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run3({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run5({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run6({
    foo: function () {
        var f = 1;
    },
    run: function () {
        var f = 1;
    }
});
run7({
    // foo is undefined here
    run: function () {
        var f = 1;
    }
});
run8({
    // foo is undefined here
    run: function () {
        var f = 1;
    }
});

results.txt

On 10 millions iteration

With the hook disabled we can compare:
--------------------------------------
109133 'function without replace'
143334 'false && function()'

result: ~23% slower by having a hook in the runtime when it is not in use.

With the hook enabled we can compare:
-------------------------------------
242666 'function with replace (with 3 func calls, original, wrapper and foo)'
219787 'true && function() (with 2 func calls, original and foo)'

result: ~10% faster by having a hook in the runtime when it is in use.


Other results:

148395 'conditional to false setting value to null'
146548 'false && function()'
2155216 'conditional to false by deleting member'
2170832 'undefined && function() by deleting member'
146075 'conditional to undefined'
146458 'undefined && function()'