bench.js

function init(size) {
    var o = {};
    for (var i=0; i<size; i++) {
        o[`some_property${i}`] = i;
    }
    return o;
}

function handler() {
    const size = Number(process.argv[2]);

    const initTime = Date.now();

    let o = init(size);

    const initEndTime = Date.now();
    const initExecutionTime = initEndTime - initTime;
}

handler();