STOP USING PERSISTENT CONNECTIONS
Persistent connections cannot be closed once open, are not pooled or recycled, and can only be closed by restarting mysql. So you very quickly run out of available connections.
We debated this extensively once and the general consensus was that persistent connections are a menace and only required, or of any use indeed, in very rare and particular circumstances, and only when a nomal connection absolutely will not work.
This is still not made clear in the manual, but it is there if you read it right.
