PHP性能：在Session中存储类对象与静态vs Globals

I've been looking for an answer on this, so far I have been unable to find an answer. My question is; What is the best way to store a huge global class that does not require any dynamic input, it only needs to be used once.

Lets take for example a template class:

<?php
class Design_API{
   function loadfile($file){
     //load file here
   }

   // do file manipulation here

   function presentfile(){
      echo($this->file);
   }

}
?>

Utilizing this class as a basic example of a layout. What would be the best way performance and security wise to use it. Would it be to create an instance of it as a global; store the instance in a session; or simply make it a static class.

Also, say we used a session if 2 clients access the site at the same exact millisecond, would php lock the session file forcing client 2's web load to take longer?

This question is a bit too mixed up to be answered in a consistent way, so here are some points:

• one client does not block another, unless they're accessing a shared resource
• sessions are not shared resources between different users, forget about this misconception
• wherever you store objects hardly makes a difference in performance
• it makes even less of a difference between different requests and users, since no resources are shared between requests
• code what you mean first and what is most maintainable, optimize this for performance later when it is proven to be slow (which it likely won't be)
• avoid globals wherever possible
• don't store stuff in the session that does not belong there, like code
• avoid static classes as much as possible, they cause code coupling, which should be reduced
• static classes are not necessarily faster

The best way to handle this is to make the class a Singleton class and use the static method to instatiante it.

Storing the object in session will involve serialization and de-serialization which is very bad for performance. Also if you store any resources in the class they can't be serialized.