CONTENTS OF THIS FILE
---------------------
* Introduction
* Usage
* Requirements and Configuration files
* Content
	- Hash Module
	- Database Module
	- Standard Module
	- String Module
	- Time Module


INTRODUCTION
------------
		PGO Train was created as an alternative to a real world workload for
	pgo train. Compared to other workloads, like WordPress, MediaWiki, Drupal,
	our project doesn't have to be installed in your computer and only external
	dependecy is Mysql. This benchmark simulates most of WordPress's execution
	path.

USAGE:
------
		In order to make this benchmark running, modify constants.php file with
	your mysql credentials.
		Before runing it for the first time, you'll have to create the database
	and this can be done running init.php (you can rerun this script whenever you
	want to bring the database to it's initial state).
		index.php is the entry point of this benchmark this is the script you'll
	want to run. In our daily measurements we used -T100 to simulate a real world
	application run.

	Eg: php -T100 /path/to/pgo_train/index.php

REQUIREMENTS AND CONFIGURATION FILES
------------
* PHP version builded with the following extensions included:
	- mysqli
	- standard
	- mbstring
	- pcre
	- date
* Configuration Files:
	- constants.php: mysql credentials are located here and should be modified
	accordingly
	- each module file contains constants that can be modified to change the
	execution time for each function inside one module.


CONTENT
-------

+--------+     +----------+     +----------+     +----------+     +------+                              
+  HASH  +<--->+ DATABASE +<--->+ STANDARD +<--->+  STRING  +<--->+ TIME +                      
+--------+     +----------+     +----------+     +----------+     +------+                     

	 	Each module has it's own register function that receives an array
	and adds it's module entry point if all the extensions required by that 
	module exist. index.php gathers all of modules entry points and starts
	executing all the registered functions. At top level of each module, 
	you can find constants that controls number of iterations for each
	function call(all of those constants were empirically set).

	1. Hash Module(dictionary.php): A set of 50 keys is used to store and increment
	values in an array.

	2. Database Module(db.php): A database connection is created and a series of
	queries are done(from simple select * from table to updates and select
	with joins). The database is created using init.php and its content is
	some random generated data. The tables format is similar to WordPress
	tables format.

	3. Standard Module(standard_calls.php): The following functions are called
	inside this module:
		error_reporting(E_ERROR | E_WARNING | E_PARSE);
		array_walk($test_array, 'do_nothing');
		krsort($test_array);
		ksort($test_array);
		parse_str($var1);
		end($test_array);
		reset($test_array);
		array_shift($test_array);
		array_pop($test_array);
		array_diff($test_array1, $test_array);
		extract($test_array, EXTR_PREFIX_SAME, "wddx");
		version_compare(phpversion(), '5.5', '>=');
		fread($file,"1024");
		fclose($file);

	4. String Module(string.php): All common string operations are done on an
	array containing 6 strings:
		preg_replace
		preg_replace_callback
		str_replace
		str_split
		md5
		trim
		implode
		mb_check_encoding

	5. Time Module(time.php): Calls strtotime and date using different formats.