Modules

Bench_LtrimDigits
extends Codebench
extends Kohana_Codebench

package
Kohana/Codebench
category
Tests
author
Geert De Deckere <[email protected]>

Class declared in MODPATH/codebench/classes/Bench/LtrimDigits.php on line 7.

Properties

public $description

Default value:
string(44) "Chopping off leading digits: regex vs ltrim."

public array $grades

Grade letters with their maximum scores. Used to color the graphs.

Default value:
array(6) (
    125 => string(1) "A"
    150 => string(1) "B"
    200 => string(1) "C"
    300 => string(1) "D"
    500 => string(1) "E"
    "default" => string(1) "F"
)

public $loops

Default value:
integer 100000

public $subjects

Default value:
array(2) (
    0 => string(9) "123digits"
    1 => string(9) "no-digits"
)

Methods

public bench_ltrim( ) (defined in Bench_LtrimDigits)

Source Code

public function bench_ltrim($subject)
{
	return ltrim($subject, '0..9');
}

public bench_regex( ) (defined in Bench_LtrimDigits)

Source Code

public function bench_regex($subject)
{
	return preg_replace('/^\d+/', '', $subject);
}

public __construct( ) (defined in Kohana_Codebench)

Constructor.

Return Values

  • void

Source Code

public function __construct()
{
	// Set the maximum execution time
	set_time_limit(Kohana::$config->load('codebench')->max_execution_time);
}

public run( ) (defined in Kohana_Codebench)

Runs Codebench on the extending class.

Return Values

  • array - Benchmark output

Source Code

public function run()
{
	// Array of all methods to loop over
	$methods = array_filter(get_class_methods($this), array($this, '_method_filter'));

	// Make sure the benchmark runs at least once,
	// also if no subject data has been provided.
	if (empty($this->subjects))
	{
		$this->subjects = array('NULL' => NULL);
	}

	// Initialize benchmark output
	$codebench = array
	(
		'class'       => get_class($this),
		'description' => $this->description,
		'loops'       => array
		(
			'base'    => (int) $this->loops,
			'total'   => (int) $this->loops * count($this->subjects) * count($methods),
		),
		'subjects'    => $this->subjects,
		'benchmarks'  => array(),
	);

	// Benchmark each method
	foreach ($methods as $method)
	{
		// Initialize benchmark output for this method
		$codebench['benchmarks'][$method] = array('time' => 0, 'memory' => 0);

		// Using Reflection because simply calling $this->$method($subject) in the loop below
		// results in buggy benchmark times correlating to the length of the method name.
		$reflection = new ReflectionMethod(get_class($this), $method);

		// Benchmark each subject on each method
		foreach ($this->subjects as $subject_key => $subject)
		{
			// Prerun each method/subject combo before the actual benchmark loop.
			// This way relatively expensive initial processes won't be benchmarked, e.g. autoloading.
			// At the same time we capture the return here so we don't have to do that in the loop anymore.
			$return = $reflection->invoke($this, $subject);

			// Start the timer for one subject
			$token = Profiler::start('codebench', $method.$subject_key);

			// The heavy work
			for ($i = 0; $i < $this->loops; ++$i)
			{
				$reflection->invoke($this, $subject);
			}

			// Stop and read the timer
			$benchmark = Profiler::total($token);

			// Benchmark output specific to the current method and subject
			$codebench['benchmarks'][$method]['subjects'][$subject_key] = array
			(
				'return' => $return,
				'time'   => $benchmark[0],
				'memory' => $benchmark[1],
			);

			// Update method totals
			$codebench['benchmarks'][$method]['time']   += $benchmark[0];
			$codebench['benchmarks'][$method]['memory'] += $benchmark[1];
		}
	}

	// Initialize the fastest and slowest benchmarks for both methods and subjects, time and memory,
	// these values will be overwritten using min() and max() later on.
	// The 999999999 values look like a hack, I know, but they work,
	// unless your method runs for more than 31 years or consumes over 1GB of memory.
	$fastest_method = $fastest_subject = array('time' => 999999999, 'memory' => 999999999); 
	$slowest_method = $slowest_subject = array('time' => 0, 'memory' => 0);

	// Find the fastest and slowest benchmarks, needed for the percentage calculations
	foreach ($methods as $method)
	{
		// Update the fastest and slowest method benchmarks
		$fastest_method['time']   = min($fastest_method['time'],   $codebench['benchmarks'][$method]['time']);
		$fastest_method['memory'] = min($fastest_method['memory'], $codebench['benchmarks'][$method]['memory']);
		$slowest_method['time']   = max($slowest_method['time'],   $codebench['benchmarks'][$method]['time']);
		$slowest_method['memory'] = max($slowest_method['memory'], $codebench['benchmarks'][$method]['memory']);

		foreach ($this->subjects as $subject_key => $subject)
		{
			// Update the fastest and slowest subject benchmarks
			$fastest_subject['time']   = min($fastest_subject['time'],   $codebench['benchmarks'][$method]['subjects'][$subject_key]['time']);
			$fastest_subject['memory'] = min($fastest_subject['memory'], $codebench['benchmarks'][$method]['subjects'][$subject_key]['memory']);
			$slowest_subject['time']   = max($slowest_subject['time'],   $codebench['benchmarks'][$method]['subjects'][$subject_key]['time']);
			$slowest_subject['memory'] = max($slowest_subject['memory'], $codebench['benchmarks'][$method]['subjects'][$subject_key]['memory']);
		}
	}

	// Percentage calculations for methods
	foreach ($codebench['benchmarks'] as & $method)
	{
		// Calculate percentage difference relative to fastest and slowest methods
		$method['percent']['fastest']['time']   = (empty($fastest_method['time']))   ? 0 : ($method['time']   / $fastest_method['time']   * 100);
		$method['percent']['fastest']['memory'] = (empty($fastest_method['memory'])) ? 0 : ($method['memory'] / $fastest_method['memory'] * 100);
		$method['percent']['slowest']['time']   = (empty($slowest_method['time']))   ? 0 : ($method['time']   / $slowest_method['time']   * 100);
		$method['percent']['slowest']['memory'] = (empty($slowest_method['memory'])) ? 0 : ($method['memory'] / $slowest_method['memory'] * 100);

		// Assign a grade for time and memory to each method
		$method['grade']['time']   = $this->_grade($method['percent']['fastest']['time']);
		$method['grade']['memory'] = $this->_grade($method['percent']['fastest']['memory']);

		// Percentage calculations for subjects
		foreach ($method['subjects'] as & $subject)
		{
			// Calculate percentage difference relative to fastest and slowest subjects for this method
			$subject['percent']['fastest']['time']   = (empty($fastest_subject['time']))   ? 0 : ($subject['time']   / $fastest_subject['time']   * 100);
			$subject['percent']['fastest']['memory'] = (empty($fastest_subject['memory'])) ? 0 : ($subject['memory'] / $fastest_subject['memory'] * 100);
			$subject['percent']['slowest']['time']   = (empty($slowest_subject['time']))   ? 0 : ($subject['time']   / $slowest_subject['time']   * 100);
			$subject['percent']['slowest']['memory'] = (empty($slowest_subject['memory'])) ? 0 : ($subject['memory'] / $slowest_subject['memory'] * 100);

			// Assign a grade letter for time and memory to each subject
			$subject['grade']['time']   = $this->_grade($subject['percent']['fastest']['time']);
			$subject['grade']['memory'] = $this->_grade($subject['percent']['fastest']['memory']);
		}
	}

	return $codebench;
}

protected _grade( integer|double $score ) (defined in Kohana_Codebench)

Returns the applicable grade letter for a score.

Parameters

  • integer|double $score required - Score

Return Values

  • string - Grade letter

Source Code

protected function _grade($score)
{
	foreach ($this->grades as $max => $grade)
	{
		if ($max === 'default')
			continue;

		if ($score <= $max)
			return $grade;
	}

	return $this->grades['default'];
}

protected _method_filter( string $method ) (defined in Kohana_Codebench)

Callback for array_filter(). Filters out all methods not to benchmark.

Parameters

  • string $method required - Method name

Return Values

  • boolean

Source Code

protected function _method_filter($method)
{
	// Only benchmark methods with the "bench" prefix
	return (substr($method, 0, 5) === 'bench');
}