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Node.js and reckless console.log() statements

I've seen code that over uses, nah rather abuses the logger. Many times teams use it in the wrong way or sometimes over use it and then struggle to improve performance. This simple test will show the effect. From the synopsis of Node.js doc, this is my server code: var http = require('http'); http.createServer(function (request, response) { response.writeHead(200, {'Content-Type': 'text/plain'}); response.end('Hello World\n'); }).listen(8124); console.log('Server running at http://127.0.0.1:8124/'); Now I use JMeter to test the performance. I fire a 1000 HTTP requests within a time frame of 2s, with a wait of 1ms duration in between each new request. In my environment the median response time was 2ms for each request. Now I add a single console log statement for the callback function in the above server code. var http = require('http'); http.createServer(function (request, response) { response.writeHead(200, {'Content...

parseInt() galore

After the Falsy post, here is another interesting table listing various values as evaluated by parseInt() . Some are quirky indeed :) Free lunch to anyone who shows me another table that covers parseInt() in such detail :P Expression Value Remarks parseInt("23") 23 parseInt(" 23") 23 Leading white space is dropped parseInt("-23") -23 parseInt(23) 23 parseInt(023) 19 Radix 8 is used parseInt(0x23) 35 Radix 16 is used parseInt("23",4) 11 Radix 4 is used parseInt("23",4.99) 11 Radix is always converted to int32 parseInt("23",36) 75 Radix 36 is used parseInt("z",36) 35 Radix 36 is used parseInt("23",37) NaN Max Radix is 36 parseInt("23",1) NaN Min Radix is 2 parseInt("23",0) 23 Radix used is 10 parseInt("23",-1) NaN Min Radix is 2 parseInt("23",3) 2 Radix 3 can use only 0,1,2 parseInt("023") 19 Radix defaults to 8 parseInt("0x23") 35 Radix defaults to...

Compress your HTML files

Updated: 2012-02-24 This is probably what every web developer knows. A very basic performance improvement for your HTML pages. You should remove all the white spaces and line breaks before you publish your html page. You can view the effect directly in a DOM inspector and this post touches the same. Consider this example available from the HTML5 spec (pg 21): <!DOCTYPE html> <html> <head> <title>Sample page</title> </head> <body> <h1>Sample page</h1> <p>This is a <a href="demo.html">simple</a> sample.</p>  </body> </html> Save it in a .html file and open in your favorite browser. Next view the DOM created by this file. You can use the DOM inspector available in most of the browsers today (launch with CTRL + SHIFT + I). You will see the below DOM tree created: ...

Sync Chrome versions and Chrome Extensions that I love

I just decided to live a little more on the edge and downloaded the Google Chrome Canary build, v13.0.x which is the developer build. But be warned, it could cause crashes though I've not faced any so far. Flash does seem to misbehave a bit ummm. Page loads are now definitely fast. Or do they seem fast to me :) Meanwhile, between various versions of Chrome, one just needs to enable sync to automatically update bookmarks, extensions .. Its easily done as follows: Click on the Wench icon on the top right and select Options->Personal Stuff Click on Set up Sync ... Enter your Google user name and password when prompted. You will be asked to Choose what to sync Select the options you prefer. I checked them all. Click on Ok and thats that. Repeat this on your new browser version and you should have all the settings, apps, extensions, themes, bookmarks everything imported, rather synced. Now here is the list of Chrome Extensions that I like and regularly use (no Orkut or Facebook her...

My Bookmarks fly to the Cloud

Updated: 15-Mar-2012 With latest version of Google Chrome (I'm using 17.x), you can now directly sign into Chrome from Options->Peronsal and access your bookmarks across computers. You no longer would need to export the bookmarks to Firefox using the Google Toolbar for Firefox, which is no longer supported by Google. The Google Toolbar is now available only for IE. Original (dated) article below ... ------- I have a queer problem of too many! I surf a lot, I subscribe to a lot and I bookmark a lot. Some numbers: 1 laptop and 1 netbook at home, 1 laptop and 1 desktop at office, sometimes its my Kindle and definitely my N900 when I'm on the move. So 6 devices out there and usually 2 browsers on most of them (yes Kindle only as one webkit based experimental implementation). So my bookmarks are all over the place, scattered over at least 10 different places. And each time I'm working on one box, I wish I had access to the bookmark I made a few hours ago on the other...

A Custom Blog and 404 errors!

I struggled for over a day with 404 errors and domain mapping issues and finally figured out the simple steps to set up my Google blog mapped to my custom domain. I also managed to add an alias to this blog site. Just jotting down the steps here for future reference ... You would've created your blog under the name say: myblog.blogspot.com Now you want to move it to your custom domain which you just purchased say: www.mydomain.com Also you might want to map blog.mydomain.com and mydomain.com to land the user on your blog page directly. The latter is called a " naked " domain and has to be handled as this is not mapped by default. Steps to create custom blog at www.mydomain.com 1. Go to your blog Dashboard (link is on the top right of your screen) 2. Select the Settings tab 3. Select the Publishing tab 4. Click on the Custom Domain link and switch to Advanced Settings 5. Enter your domain name here www.mydomain.com 6. Check the " Redirect myd...

Falsy JavaScript

In continuation of my previous blog on the basic JavaScript expressions , this blog is about Falsy and Truthy values in JavaScript. When presented with a non boolean expression instead of a boolean value, JavaScript uses Truthy or Falsy values instead to determine the result. At first glance, this could be confusing and could lead to errors while scripting. var a = "someval"; var b; if (a) { // this is a truthy // Block is executed } if (b) { // b is undefined and so a falsy // Block is not executed } The Falsy Values All expressions, objects and values are Truthy by default. There are exceptions and they are called the Falsy values and are listed below: # The empty string; "" # null # undefined # The number 0 # NaN # The boolean false It gets tricky If you see the below table, you will note that it gets tricky or rather one should be a l...