Php under the_hood
- 1. PHP under the hood Frank Neff
- 2. PHP
- 3. is
- 4. compiled
- 5. at
- 6. runtime!
- 7. Source code you write...
- 9. Kidding me?
- 10. Looks confusing, but this is... ● how PHP works ● cool for debugging purposes ● visualizing code complexity ● helpful trying to understand opcaches like APC
- 11. Try it with your code http://explain.php.net.so
- 12. So this is about profiling?
- 13. No! XHProf is about profiling ● XHProf is a function-level hierarchical profiler for PHP ● Reports timing information for every function called ● C-Extension can be loaded via PECL ● GUI and libs available
- 14. Looks like this
- 15. Try it with your code http://xhprof.io/
- 17. Compiling at runtime is slow!
- 18. OpCode Cache ● Performance enhancing extension for PHP ● Hooking into the execution life-cycle ● Caching the results of the compilation phase for later reuse ● APC ● XCache
- 19. HHVM ● HipHop Virtual Machine ● Designed for executing PHP programs ● Predecessor HPHPc makes C out of PHP ● Uses a just-in-time (JIT) compilation ● http://www.hhvm.com/
- 23. Kidding me?
- 24. No! ● Namespaces in PHP are just class-prefixes ● They are added to each classname by the compiler ● The result is called a FQCN - Fully Qualified Class Name
- 28. What do you think of copy & paste code?
- 30. What do you think of traits?
- 32. Cool. Traits are for... ● Code reusage ● Multiple inheritance ● Keeping stuff you often use in different contexts ● No need for complex OOP architectures
- 33. Nooooooo!
- 34. Seriously...
- 35. No.
- 36. No. Because traits are... ● Copied into every single class at compile- time ● Therefore not runtime bindable ● Not testable ● Tightly coupled ● Make it easier to cross SRP (one god-class)
- 37. (traits === copy & paste)
- 38. Wanna read more? ● PHP at the Core: A Hacker's Guide ● PHP Compiler Internals ● PHP OpCodes ● PHP Internals ● Are Traits The New Eval? ● PHP-RFC’s
- 39. So you’re telling me not to use such cool features in PHP?
- 40. No. Just be aware of how things work in PHP while writing code