Use a basic time tracker instead of Date manipulation

lib/profiler.js

@@ -0,0 +1,31 @@
+var logger = require('./logger');
+
+var timestamps = {};
+
+function getCurrentTimeMs() {
+    return (new Date).getTime();
+};
+
+exports.track = function(name) {
+    if (timestamps[name]) {
+        throw new Error(name + ' is already being profiled!');
+    }
+
+    timestamps[name] = getCurrentTimeMs();
+};
+
+exports.untrack = function(name) {
+    if (!timestamps[name]) {
+        throw new Error(name + ' isn\'t being profiled!');
+    }
+
+    var timestamp = getCurrentTimeMs() - timestamps[name];
+
+    delete timestamps[name];
+
+    logger.log('debug', name + ' took ' + timestamp + 'ms');
+
+    return timestamp;
+};
+
+exports.getCurrentTimeMs = getCurrentTimeMs();