Question

I have something like a microtime() function at the very start of my node.js / express app.

function microtime (get_as_float) {
    // Returns either a string or a float containing the current time in seconds and microseconds  
    // 
    // version: 1109.2015
    // discuss at: http://phpjs.org/functions/microtime
    // +   original by: Paulo Freitas
    // *     example 1: timeStamp = microtime(true);
    // *     results 1: timeStamp > 1000000000 && timeStamp < 2000000000
    var now = new Date().getTime() / 1000;
    var s = parseInt(now, 10);

    return (get_as_float) ? now : (Math.round((now - s) * 1000) / 1000) + ' ' + s;
}

The code of the actual app looks something like this:

application.post('/', function(request, response) {
  t1 = microtime(true);
  //code
   //code
   response.send(something);
   console.log("Time elapsed: " + (microtime(true) - t1));
}

Time elapsed: 0.00599980354309082

My question is, does this mean that from the time a POST request hits the server to the time a response is sent out is give or take ~0.005s?

I’ve measured it client-side but my internet is pretty slow so I think there’s some lag that has nothing to do with the application itself. What’s a quick and easy way to check how quickly the requests are being processed?

Answer 1

Shameless plug here. I’ve written an agent that tracks the time usage for every Express request.

http://blog.notifymode.com/blog/2012/07/17/profiling-express-web-framwork-with-notifymode/

In fact when I first started writing the agent, I took the same approach. But I soon realized that it is not accurate. My implementation tracks the time difference between request and the response by substituting the Express router. That allowed me to add tracker functions. Feel free to give it a try.