speed up and optimise php code
30 Nov 2009 by Steve
- If a method can be static, declare it static. Speed improvement is by a factor of 4.
- echo is faster than print.(* compare with list from phplens by John Lim)
- 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
- str_replace is faster than preg_replace, but strtr is faster than str_replace by a factor of 4
- If the function, such as string replacement function, accepts both arrays and single characters as arguments, and if your argument list is not too long, consider writing a few redundant replacement statements, passing one character at a time, instead of one line of code that accepts arrays as search and replace arguments.
- It’s better to use select statements than multi if, else if, statements.
- Error suppression with @ is very slow.
- Turn on apache’s mod_deflate
- Close your database connections when you’re done with them
- $row[’id’] is 7 times faster than $row[id]
- Error messages are expensive
- Do not use functions inside of for loop, such as for ($x=0; $x < count($array); $x) The count() function gets called each time.
