How to Calculate a PHP script’s memory usage In PHP

If you want to know how much memory PHP script uses, then in this case in PHP there is a great in-built function that is memory_get_usage().

memory_get_usage :
memory_get_usage() — Returns the amount of memory allocated to PHP

Description :
int memory_get_usage ([ bool $real_usage = false ] )
Returns the amount of memory, in bytes, that’s currently being allocated to your PHP script.

Parameters :
Set this to TRUE to get the real size of memory allocated from system. If not set or FALSE only the memory used by emalloc() is reported.

Return Values :
Returns the memory amount in bytes.

Example :

// Displays the amount of memory being used as soon as the script runs
echo memory_get_usage() . "<br/>";   // Returns 46552 Bytes

//Your code goes here
$a = str_repeat('Avinash Pawar', 10000);

// Displays the amount of memory being used by your code
echo memory_get_usage() . "<br/>"; // Returns 176636 Bytes

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