Facebook Javascript SDK の読み込みと初期化速度を測定

以下このページで利用しているjavascript。
    var millsec = 0;
    function logging(message) {
      $("#log").append("
log : " + message + ": wait " + (+new Date() - millsec).toString() + " millisecond
"); } function initFacebookAPI(loadedHandler) { millsec = +new Date(); window.fbAsyncInit = function() { logging("start fbAsyncInit"); FB.init({ xfbml: false, version: 'v2.7' }); logging("finish fbAsyncInit"); loadedHandler(); }; (function(d, s, id) { logging("facebook-jssdk"); var js, fjs = d.getElementsByTagName(s)[0]; if (d.getElementById(id)) { return; } js = d.createElement(s); js.id = id; js.src = "https://connect.facebook.net/en_US/sdk.js"; fjs.parentNode.insertBefore(js, fjs); }(document, 'script', 'facebook-jssdk')); } initFacebookAPI( function() { document.getElementById('show-fb-share-button').onclick = function() { millsec = +new Date(); logging("start FB.XFBML.parse"); FB.XFBML.parse(document.body, function() { logging("finish FB.XFBML.parse"); }); }; } );
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