How to setup a stress test on Oracle or equivalent databases

In a recent workshop on Oracle12c administration, I noticed that the participants had no idea how to let Oracle create archived redo logfles, i.e. they did not know how to create a relevant workload. In the exercises of the workshops you can find one, which performs some workload on CPU and I/O, but nothing about writing so much to the online redo logs, that the log writer process LGWR needs to copy the contents to the archived redo log files.
In summary, the students - all computer scientists working several years in IT companies - had never seen a stress test before. To solve the issue, I passed an old script of mine to them. To whom it may concern, I will publish it here, because it is really simple.

No bug in oracle-rdbms-server-12cR1-preinstall !

This refers to my last post bug or feature in oracle -rdbms-server-12cR1-preinstall
There is no problem in oracle-rdbms-server-12cR1-preinstall, but rather a little confusion in the docker image breed85/oracle-12:preinstall.

bug or feature in oracle-rdbms-server-12cR1-preinstall?

The latest version of oracle-rdbms-server-12cR1-preinstall introduces an interesting behaviour: it blocks su - oracle with the vacuous message su: could not open session. But we really need to be able to do that, when we want to install Oracle12c.
There are many questions and answers in the net trying to get rid of that extremely annoying issue. Here is the solution.

"Docker is managed via upstart, try using service docker restart" - baffling advice ?

Presumably every docker user has already followed this advice and experienced a baffling message "unkown job docker". There are quite a lot of questions and some bug reports in the net, but seemingly no satisfying answers. The question seems to me: "What is upstart?" Here is my own workaround.