The pre-existing users in the MaxScale test environment have
the super privilege so they are not affected by the database
being set in read-only mode.
Consequently, a custom user without the super privilege must
be used by the client threads.
- Start 4 threads where each thread sits in a loop and performs
20% updates and 80% selects. Each thread has a table of its own.
- The main thread executes the following in a loop.
- Perform a switchover from the current master to the next (which is
simply the next node % all nodes).
- Keep on doing that for 1.5 minutes.
The expectation is that the switchover will succeed, that is, after the
operation there will be a new master.