CI Framework Source Code Reading Notes 5 Benchmark Test BenchMark.php_PHP Tutorial

CI Framework Source Code Reading Notes 5 Benchmark Test BenchMark.php

Since BenchMark is the first core component loaded in CI, our analysis starts from this component first. The meaning of BenchMark is very clear. Students who have used the BenchMark tool should know that this is a benchmark component. Since it is BenchMark, we can boldly guess that the main function of the BM component is to record the running time, memory usage, CPU usage, etc. of the program.

The structure of this component is relatively simple, with only one marker internal variable and three external interfaces:

1 Elapsed_time

2 Mark

3 Memory_usage

Expand each one below:

1.mark

The signature of the function is:

function mark($name)

This function accepts a string type parameter, and the implementation is simpler, with only one sentence:

$this->marker[$name] = microtime();

In other words, this function is only used to record the time point at which the function is called.

It is worth noting that due to the special processing in the Controller (we will explain it in detail later), you can use $this->benchmark->mark($name); to add it to your application controller. The running time point, for example:

$this->benchmark->mark("function_test_start");

$this->_test();

$this->benchmark->mark("function_test_end");

print_r($this->benchmark);

Among them, function_test_start and function_test_end are used to record the start and end time points of function calls respectively

Printed results:

Now to calculate the function call time, you need to use the second function elapsed_time of the BenchMark component

2. elapsed_time

The signature of the function is:

function elapsed_time($point1 = '', $point2 = '', $decimals = 4)

All three parameters are optional

(1). If $point1 is empty, return ‘{elapsed_time}’

if ($point1 == '') {

return '{elapsed_time}';

}

Nani! It should obviously return time, but instead it returns a string, and it’s so strange (similar to smarty tags). In fact, in the Output component, {elapsed_time} will be replaced. Let’s take a look at the replacement method for now:

$elapsed = $BM->elapsed_time('total_execution_time_start', 'total_execution_time_end');

$output = str_replace('{elapsed_time}', $elapsed, $output);

In other words, when no parameters are specified, what is actually obtained by calling this function is the time difference from the total_execution_time_start time point to the total_execution_time_end time point. Furthermore, since total_execution_time_start is the first mark point set after BM is loaded (total_execution_time_end is not defined and returns the current time point), what this function returns is actually the loading and running time of the system.

(2). If an unknown mark point is called. The result is unknown and empty is returned directly:

if ( ! isset($this->marker[$point1]))

{

return '';

}

(3). If the mark point of $point2 is not set, set the mark point of $point2 to the current time point.

if ( ! isset($this->marker[$point2]))

{

$this->marker[$point2] = microtime();

}

(4). The time difference between the last two mark points returned:

list($sm, $ss) = explode(' ', $this->marker[$point1]);

list($em, $es) = explode(' ', $this->marker[$point2]);

return number_format(($em + $es) - ($sm + $ss), $decimals);

Looking at the previous example, here we can call:

echo $this->benchmark->elapsed_time("function_test_start","function_test_end");

Get the execution time of the function.

3. memory_usage

This function returns the memory usage of the system (MB unit). Like {elapsed_time}, the {memory_usage} returned by this function will also be replaced in Output:

$memory = ( ! function_exists('memory_get_usage')) ? '0' : round(memory_get_usage()/1024/1024, 2).'MB';

$output = str_replace('{memory_usage}', $memory, $output);

Since the BenchMark component itself is relatively simple, we will not explain it further.

Finally, paste the source code of this component:

Copy code

class CI_Benchmark {

/**

     * List of all benchmark markers and when they were added

     *

     * @var array

     */

var $marker = array();

/**

     * Set a benchmark marker

     *

     * @access    public

     * @param    string    $name    name of the marker

     * @return    void

     */

function mark($name)

{

$this->marker[$name] = microtime();

}

/**

     * Calculates the time difference between two marked points.

     * If the first parameter is empty this function instead returns the {elapsed_time} pseudo-variable. This permits the full system

     * @access    public

     * @param    string    a particular marked point

     * @param    string    a particular marked point

     * @param    integer    the number of decimal places

     * @return    mixed

     */

function elapsed_time($point1 = '', $point2 = '', $decimals = 4)

{

if ($point1 == '')

{

                  return '{elapsed_time}';

}

if ( ! isset($this->marker[$point1]))

{

          return '';

}

if ( ! isset($this->marker[$point2]))

{

$this->marker[$point2] = microtime();

}

list($sm, $ss) = explode(' ', $this->marker[$point1]);

list($em, $es) = explode(' ', $this->marker[$point2]);

return number_format(($em + $es) - ($sm + $ss), $decimals);

}

/**

     * Memory Usage

     * This function returns the {memory_usage} pseudo-variable.

     */

function memory_usage()

{

return '{memory_usage}';

}

}

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