Buffer.concat(list) vs str += buf.toString()

buffer.concat_vs_buf.toString.js

var chunks = 10000;
var buf;

buf = new Buffer(4069);
buf.fill('a', 0, 4069);

(function(){
    var arr = [],
        concated,
        j = 0;

    console.time('buffer.concat');

    for( ; j <= 10000; j++){
        arr.push(buf);
    }

    concated = Buffer.concat(arr);

    console.timeEnd('buffer.concat');
})();

(function(){
    var concated = '',
        j = 0;                                                                                                                                                                                                 

    console.time('string.concat');

    for( ; j <= 10000; j++){
        concated += buf.toString();
    }

    console.timeEnd('string.concat');
})();
~