Database Connection Pooling with Smart Reset

Sun, 09 Aug 2026 16:25:00 -0700

PHP’s share-nothing model is one of its best properties. It has one expensive side effect: a request can’t keep a database connection for the next request. php-fpm gives you PDO::ATTR_PERSISTENT and mysqli’s p: hosts. But those are per-worker-process. PDO’s keep whatever session state the last request left behind. mysqli at least resets the session with COM_CHANGE_USER on reuse. And almost nobody turns them on. So in practice every PHP request does a TCP connect, a MySQL handshake and an auth exchange. Then it maybe sends some SETs, runs its queries and sends COM_QUIT. Multiply that by your request rate and MySQL spends a real share of its time authenticating clients it just said goodbye to.

Connection Pooling on Luther Monson

Database Connection Pooling with Smart Reset