About the management of arrays and memory in PHP

About the management of arrays and memory in PHP
According to the manual, php except object, other types of variables in the assignment, parameter passing, return value is a copy of it
But look at the following test, do not know because the test method is a problem, or if it is not used & by reference, or share the same part of memory, but after changing its elements to actually generate a copy out?




------Solution--------------------
It's not clear what your goal is.

m = 0;
$m = Memory_get_usage ();
$t = array (' id ' = = 1, ' name ' = ' None ');
Echo ' $t occupancy: ', Memory_get_usage ()-$m, Php_eol;
$data = Array ();
Echo ' Empty $data occupy: ', Memory_get_usage ()-$m, Php_eol;
$m = Memory_get_usage ();
for ($i =0; $i <1000; $i + +) {
  $data [] = null;
}
echo ' 1000 empty elements $data occupied: ', Memory_get_usage ()-$m, Php_eol;
$data = Array ();
$m = Memory_get_usage ();
for ($i =0; $i <1000; $i + +) {
  $data [] = $t;
}
Echo ' 1000 $t elements of $data occupy: ', Memory_get_usage ()-$m, Php_eol;
$data = Array ();
$m = Memory_get_usage ();
for ($i =0; $i <1000; $i + +) {
  $data [] = array (' id ' = = 1, ' name ' = ' None ');
}
$data occupancy of ECHO ' 1000 entity elements: ', Memory_get_usage ()-$m, Php_eol;

$t Occupation: 360
Empty $data Occupation: 496
$data occupancy of 1000 empty elements: 84200
$data occupancy of 1000 $t elements: 52104
$data occupancy of 1000 entity elements: 356136

It might be clearer.
------Solution--------------------
Reference:

Of course, that is the surface phenomenon, I want to know how to manage the memory of PHP, there is no official information what, or can only see the source of PHP?

Hash table
------Solution--------------------
PHP variables are copied at the time of writing
Look at this article: http://www.laruence.com/2008/09/19/520.html

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