What is the fastest way to clone/copy oracle databases on the same machine? I want to clone oracle databases on the same machine and
I need to change user etc. from e.g. PROD to DEV.
For that I use expdp/impdp, but this tends to be slow with increasing database size.
I need to do this on linux and windows machines.

Is using expdp/impdp the fastest way to do this?

Or should I use a completly different way of doing this?
rman is the tool for this.

https://docs.oracle.com/cd/E11882_01/backup.112/e10642/toc.htm

There is a learning curve, but once configured, it's much faster than export/import.