<?php
/**
* CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
*
* Licensed under The MIT License
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
* @link http://cakephp.org CakePHP(tm) Project
* @since DebugKit 1.0
* @license http://www.opensource.org/licenses/mit-license.php MIT License
*/
namespace DebugKit\Shell;
use Cake\Console\Shell;
use Cake\Utility\Text;
/**
* Benchmark Shell Class
*
* Provides basic benchmarking of application requests
* functionally similar to Apache AB
*
* @since DebugKit 1.0
*/
class BenchmarkShell extends Shell
{
/**
* Main execution of shell
*
* @return void
*/
public function main()
{
$url = $this->args[0];
$defaults = ['t' => 100, 'n' => 10];
$options = array_merge($defaults, $this->params);
$times = [];
$this->out(Text::insert(__d('debug_kit', '-> Testing :url'), compact('url')));
$this->out("");
for ($i = 0; $i < $options['n']; $i++) {
if (floor($options['t'] - array_sum($times)) <= 0 || $options['n'] <= 1) {
break;
}
$start = microtime(true);
file_get_contents($url);
$stop = microtime(true);
$times[] = $stop - $start;
}
$this->_results($times);
}
/**
* Prints calculated results
*
* @param array $times Array of time values
* @return void
*/
protected function _results($times)
{
$duration = array_sum($times);
$requests = count($times);
$this->out(Text::insert(__d('debug_kit', 'Total Requests made: :requests'), compact('requests')));
$this->out(Text::insert(__d('debug_kit', 'Total Time elapsed: :duration (seconds)'), compact('duration')));
$this->out("");
$this->out(Text::insert(__d('debug_kit', 'Requests/Second: :rps req/sec'), [
'rps' => round($requests / $duration, 3),
]));
$this->out(Text::insert(__d('debug_kit', 'Average request time: :average-time seconds'), [
'average-time' => round($duration / $requests, 3),
]));
$this->out(Text::insert(__d('debug_kit', 'Standard deviation of average request time: :std-dev'), [
'std-dev' => round($this->_deviation($times, true), 3),
]));
$this->out(Text::insert(__d('debug_kit', 'Longest/shortest request: :longest sec/:shortest sec'), [
'longest' => round(max($times), 3),
'shortest' => round(min($times), 3),
]));
$this->out("");
}
/**
* One-pass, numerically stable calculation of population variance.
*
* Donald E. Knuth (1998).
* The Art of Computer Programming, volume 2: Seminumerical Algorithms, 3rd edn.,
* p. 232. Boston: Addison-Wesley.
*
* @param array $times Array of values
* @param bool $sample If true, calculates an unbiased estimate of the population
* variance from a finite sample.
* @return float Variance
*/
protected function _variance($times, $sample = true)
{
$n = $mean = $M2 = 0;
foreach ($times as $time) {
$n += 1;
$delta = $time - $mean;
$mean = $mean + $delta / $n;
$M2 = $M2 + $delta * ($time - $mean);
}
if ($sample) {
$n -= 1;
}
return $M2 / $n;
}
/**
* Calculate the standard deviation.
*
* @param array $times Array of values
* @param bool $sample ''
* @return float Standard deviation
*/
protected function _deviation($times, $sample = true)
{
return sqrt($this->_variance($times, $sample));
}
/**
* Get option parser.
*
* @return \Cake\Console\ConsoleOptionParser
*/
public function getOptionParser()
{
$parser = parent::getOptionParser();
$parser->description(__d(
'debug_kit',
'Allows you to obtain some rough benchmarking statistics' .
'about a fully qualified URL.'
))
->addArgument('url', [
'help' => __d('debug_kit', 'The URL to request.'),
'required' => true,
])
->addOption('n', [
'default' => 10,
'help' => __d('debug_kit', 'Number of iterations to perform.'),
])
->addOption('t', [
'default' => 100,
'help' => __d(
'debug_kit',
'Maximum total time for all iterations, in seconds.' .
'If a single iteration takes more than the timeout, only one request will be made'
),
])
->epilog(__d(
'debug_kit',
'Example Use: `cake benchmark --n 10 --t 100 http://localhost/testsite`. ' .
'<info>Note:</info> this benchmark does not include browser render times.'
));
return $parser;
}
}