Just came across this really nice article.
I knew several of them, but there's a few new interesting ones I'll test on my next PHP programming project..
- If a method can be static, declare it static. Speed improvement is by a factor of 4.
- echo is faster than print.
- Use echo's multiple parameters instead of string concatenation.
- Set the maxvalue for your for-loops before and not in the loop.
- Unset your variables to free memory, especially large arrays.
- Avoid magic like __get, __set, __autoload
- require_once() is expensive
- Use full paths in includes and requires, less time spent on resolving the OS paths.
- If you need to find out the time when the script started executing, $_SERVER[’REQUEST_TIME’] is preferred to time()
- See if you can use strncasecmp, strpbrk and stripos instead of regex
More here:
http://reinholdweber.com/?p=3