jfbus writes "PHP, like all scripting languages, suffers from having to parse all script files each time a page is displayed. Accelerators (opcode caches) are necessary to speed PHP enough for large websites. Here is a benchmark of the major PHP accelerators (Zend platform, apc and eAccelerator)."
The most difficult thing in the world is to know how to do a thing and to
watch someone else doing it wrong, without commenting.
-- T.H. White