2008 August » Think Lamp

Fork Bomb

Aug 182008

A fork bomb works by creating a large number of processes very quickly in order to saturate the available space in the list of processes kept by the computer’s operating system. If the process table becomes saturated, no new programs may be started until another terminates.

WikiPage : http://en.wikipedia.org/wiki/Fork_bomb

while(1)
pcntl_fork();

Note: Process Control support in PHP is not enabled by default. You have to compile the CGI or CLI version of PHP with –enable-pcntl configuration option when compiling PHP to enable Process Control support.
Currently, this module will not function on non-Unix platforms (Windows).

Sieve of Eratosthenes in PhP

PHP 21 Responses »

Aug 122008

Prime Numbers: Positive natural numbers which has exactly two distinct natural number divisors 1 and itself.

Sieve Of Eratosthenes is a computer algorithm to find out prime numbers upto a specified integer starting from 2.
The time complexity of a unfaithful sieve is Θ(n2/(log n)2) ( regardless of what wikipedia might say )

Basic dead lock example

PHP 2 Responses »

Aug 122008

A deadlock is a situation wherein two or more competing actions are waiting for the other to finish, and thus neither ever does. It is often seen in a paradox like ‘the chicken or the egg‘.