title: Does PHP support "Application Sessions"?
body: <p>I've got a PHP app that stores arbitrary config info in a file. I would like to read that file once, when the app first starts, save it as some kind of application state variable, and leverage it across potentially thousands of user sessions. My Google foo is usually pretty good but in this case the only thing I'm able to come up with is the <code>$_SESSION</code> variable. Using it means reading the config file once <em>per user session</em>, which could mean reading it thousands of times a minute in high-volume installations, which seems inefficient.</p>
  
  <p>When I worked with .NET web apps there was an idea of an <a href="https://msdn.microsoft.com/en-us/library/ms952597.aspx?f=255&amp;MSPPError=-2147217396" rel="nofollow noreferrer">application session</a> that could be used to persist app configuration information across multiple user sessions. Does PHP have a similar concept?</p>