memory_get_usage
(PHP 4 >= 4.3.2, PHP 5, PHP 7, PHP 8)
memory_get_usage —
Returns the amount of memory allocated to the PHP script, or reserved
from the system by PHP's memory manager
Description
Returns the amount of memory, in bytes, that is currently allocated to
the PHP script by PHP's memory manager. The reported value is rounded up
to the granularity of the allocator, so it is larger than the exact
number of bytes that were requested.
Parameters
real_usage
-
Set this to true to get the total amount of memory that PHP's memory
manager has reserved from the system, including pages that are not
currently in use. This is the value that
memory_limit is enforced
against. It is not the amount of memory the operating system has given
to the PHP process, which is typically much larger.
If not set or false only the memory currently allocated to the PHP
script is reported.
Note:
PHP only tracks memory allocated through its own memory manager, that is
through the internal emalloc() function and the related
ones. Memory allocated persistently, or directly with
malloc() by an extension, is not reported, even when
real_usage is true.
Return Values
Returns the memory amount in bytes.
Examples
Example #1 A memory_get_usage() example
<?php
// This is only an example, the numbers below will
// differ depending on the specific system
echo memory_get_usage(), "\n"; // 36640
$a = str_repeat("Hello", 4242);
echo memory_get_usage(), "\n"; // 57960
unset($a);
echo memory_get_usage(), "\n"; // 36744
?>