test rect performance

HTML

<canvas id="canvas" width=400 height=400></canvas>

JavaScript

// requestAnimationFrame polyfill
(function () {
    var lastTime = 0;
    var vendors = ['webkit', 'moz'];
    for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
        window.requestAnimationFrame = window[vendors[x] + 'RequestAnimationFrame'];
        window.cancelAnimationFrame = window[vendors[x] + 'CancelAnimationFrame'] || window[vendors[x] + 'CancelRequestAnimationFrame'];
    }

    if (!window.requestAnimationFrame) window.requestAnimationFrame = function (callback, element) {
        var currTime = new Date().getTime();
        var timeToCall = Math.max(0, 16 - (currTime - lastTime));
        var id = window.setTimeout(function () {
            callback(currTime + timeToCall);
        },
        timeToCall);
        lastTime = currTime + timeToCall;
        return id;
    };

    if (!window.cancelAnimationFrame) window.cancelAnimationFrame = function (id) {
        clearTimeout(id);
    };
}());

(function () {

    var canvas = document.getElementById("canvas");
    var canvasContext = canvas.getContext("2d");
    var cw = canvas.width;
    var ch = canvas.height;

    var fps = 0,
        timeBetweenFrames = 0,
        lastTime = 0;

    function drawText() {
        canvasContext.fillStyle = "#FCEB77";
        canvasContext.fillText('  Score: ' + 66 + '  Lives: ' + 66 + ' other info: ' + 66, 10, 45);
    }

    function drawRects() {
        //canvasContext.beginPath();
        canvasContext.rect(2, 1, 210, 30);
        canvasContext.rect(2, 1, 80, 30);
        canvasContext.rect(80, 1, 70, 30);
        canvasContext.strokeStyle = "#FCEB77";
        canvasContext.stroke();
        //canvasContext.closePath();
    }

    function renderLoop(timeElapsed) {

        timeBetweenFrames = timeElapsed - lastTime;
        fps = Math.round(1000 / timeBetweenFrames);
        lastTime = timeElapsed;

        canvasContext.clearRect(0, 0, cw - 200, ch);

        drawText();
        drawRects();

       ...