PHP does not support the use of pooled connections at all, using any database.
This is because its (flexible) architecture prevents them from working, as the (potentially) multiprocess model does not allow processes to share connections.
the _pconnect functions do not use pooled connections, they use persistent connections, which are not the same thing and should be used with extreme caution.
With persistent connections it is possible to break your application or server(s) easily in a variety of ways which could be difficult to debug.
Connection to mysql is normally a very quick operation (some exceptions apply though, such as if you're using SSL or a slow network), therefore it does not slow your application down much.
If your benchmark data* prove to you that you absolutely require persistent connections, consider using either PDO or mysql_ functions.
Mark
- You do have concrete benchmarks of your own application, which show the performance benefit of using persistent connections in a load testing scenario, don't you?
