A must read for PHP Programmers. Here is the first half:
- If a method can be static, declare it static. Speed improvement is by a factor of 4.
- echo is faster than print.
- 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.
- Error suppression with @ is very slow.
- $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.
- Incrementing a local variable in a method is the fastest. Nearly the same as calling a local variable in a function.
- Incrementing a global variable is 2 times slow than a local var.
- Incrementing a object property (eg. $this->prop++) is 3 times slower than a local variable.
- Incrementing an undefined local variable is 9-10 times slower than a pre-initialized one.
- Just declaring a global variable without using it in a function also slows things down (by about the same amount as incrementing a local var). PHP probably does a check to see if the global exists.
For the other half, go here.
Where is other 20 tips ?
looks like it got lost. the last link is supposed to be here: http://reinholdweber.com/?p=3
Ha, looks like you should add one for how to optimize pagination