Monday, 21 April 2014

Facebook facts

                                   

Which is the biggest social network in this virtual-cosmos?
“Facebook”
Obviously, there is no doubt in it. Facebook is the only social network in the world that crossed billion users on. Each and every individual has their Facebook account; even the kid’s making their 4th grade in school. We may ask is it really Facebook has this much of user’s account and maintaining those people? Yes is the answer Facebook has billions of users and giving the information which is saved by people every day. So, how this much of data of a billion people are stacked away?
Let see how and what Facebook is actually doing?
One Data scientist for one million users 
Facebook has several working Data scientist (engineers) to maintain the data provided by and for the masses. In the data centre of Facebook, Each data scientist takes care of one million user’s data. It's very interesting about this allotment of data with the applied data scientist. We are getting out maintaining one system (PC). Think how they are doing It.!
Data Centre
The important thing to maintain the data is placed. Where the data is actually laid in? It is Facebook data center. Facebook has 300,000 square feet comes Data centre to give space for the memory disks. The memory size of the data is equal to 3 full Football field space. 100+ million dollars spent to build this data center. 
This data racks are winded up with 21 million feet, fiber optical cables. 

Power Consumption
How much electricity is demanded for this data centre? In our home, if the power cut came at the time of copying or moving the files from disk. What exactly will happen? For a modest amount of data transfer, we need power for it. Then what about data of billion users? Yes, Lots of power is needed for this data center. It is about 30 Mega Watt of power that is needed for the whole data centre to go on in.
In the back up, 14 numbers of 3 Megawatt generators are at the place there. 

Servers Conditioning
The host server has to maintain the temperature to keep response every time if you request “www.facebook.com” on your browser. If the temperature is not maintained, then the server will burn this day or night. So, Air conditioners were fitted to 7 rooftops to maintain the temperature.
How many people are logging in everyday?
For a day, the people logging on to Facebook are equal to twice the population of the United States.
For this reason, Facebook buys 1000 new servers every day. Each server has many racks. Each rack contains 500 TB of memory space. 500 TB is equals to 130 billion times greater than the memory space of an apple’s first pc.
The above specs are out of usage for Facebook data. So new buildings are being built
How the request is processed so fast even the website is PHP?
We all heard Facebook is built with PHP codes. But actually it works on C++; you can check it on Wikipedia. This is done by a specially made compiler called “Hip-Hop” Compiler. HipHop for PHP isn't technically a compiler itself. Rather it is a source code transformer. HipHop programmatically transforms your PHP source code into highly optimized C++ and then uses g++ to compile it. HipHop executes the source code in a semantically equivalent manner and sacrifices some rarely used features.
                                                                

                                 One More Thing.