[转载]12 PHP optimization tips

原始链接：http://www.moskalyuk.com/blog/php-optimization-tips/1272

Ilia Alshanetsky’s PHP performance talk given last week at the Zend conference is pretty useful as far as getting small tips for tweaking PHP code.

If a method can be static, declare it static. Speed improvement is by a factor of 4.
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
preg_replace is faster than str_replace, but strtr is faster than preg_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.
For templating, are you using Smarty? This is probably the fastest way to ensure the frequently viewed pages of the site are cached.