I don't know anything about the Oracle module but using Pike on a SMP machine is useless since there is a global interpret lock in Pike so it can only use one CPU at a time.

Except of course when the C-module allows for concurrent operations e.g. when making SQL queries, processing images, hashing data and other operations that doesn't affect Pike structures until completed.

On a webserver the OS and the DBM typically also needs CPU time, and they are not bound by the intepretator lock.