It's not a problem, it's a trade-off. An architecture that doesn't keep state across requests trades off per-request performance for stability and scalability,

It's not a problem, it's a trade-off. An architecture that doesn't keep state across requests trades off per-request performance for stability and scalability, because there is no long-term state on the web server to manage or migrate. CGI traded off too much performance because of the need to launch a process per request, but fastcgi keeps the process alive but throws away the state, so i find the upside beats the downside in a lot of cases (sadly not all, i wish php was less opinionated here, like java where you can choose to have a stateless architecture but don't have to.)