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PHP

Pragmatic server-side language that powers a large share of the web.

Paradigm

OOP, procedural, functional features

Typing

Dynamic with gradual typing (strict_types)

Memory

Reference counting + cycle collector

Runs

Zend Engine, bytecode + OPcache, optional JIT

Concurrency

Shared-nothing per request; Fibers (8.1)

Performance

How PHP runs, and what that means in practice.

Source is compiled to opcodes and cached by OPcache; a JIT exists since PHP 8.0 and helps CPU-bound code more than typical web requests.

Reference counting frees most memory immediately; everything is released at the end of a request.

Concurrency through many worker processes (PHP-FPM); Fibers enable async libraries such as ReactPHP and AMPHP.

PHP 7 and 8 were major speed-ups over PHP 5. Bootstrapping the framework on every request is often the main cost; long-running servers remove it.

Saved in this browser only. Part of From code to production (0/5).