internals
Two hundred thousand objects, and the collector never ran
Two hundred thousand objects created and dropped, and zero collections. What puts an object in the root buffer, and why the collector's cost is set by what you keep alive.
Internals
The engine: compilation, the Zend VM, memory layout, and the data structures behind the values you pass around.
5 posts
internals
A by-reference foreach leaves a reference in every element
Walking an array with foreach ($rows as &$row) wraps every element in a zend_reference. On a million integers that is 32 MB the loop never gives back.
internals
What a PHP variable actually is
A zval is sixteen bytes, a value union and a type tag. What that tag says decides whether an assignment copies anything, what a reference costs, and which variable pays.
internals
PHP arrays are not arrays
One structure serves as list, dictionary and set. Packed and hashed layouts, what each costs in memory, and when a conversion happens.
internals
What happens when PHP runs your code
A request walks from the SAPI to the Zend VM — lexing, compilation to opcodes, the OPcache lookup that skips both, and execution.