When developing a Web app with PHP, especially when using a framework or a CMS, most often you just don’t care about sessions. Less frequently, you store and access some information from a session, accessing it via language constructs (like “singleton” object (e.g.
ZendSession in Zend framework), some special wrapper functions or just
$_SESSION global). More often, though, you don’t bother monitoring how and where sessions are stored. But sometimes you should.
The basic purpose of this post is to talk about how, when developing a high-load website, to allow users to log on and access some personalized information. When you have hundreds of thousands hits per day, you should expect that tens of thousands users will log in to their respective accounts. That’s when you need to start caring about session storage. Continue reading