Right now the default values between Carpet and PUGH (who both implement) "Driver" differ (see
#745). Since they should not (for reasons that it prevents users from easily switching from one to the other and because the current Cactus implementation has a bug when handling this case) and because Carpet (which does not even support periodic boundary conditions in this manner) is by far the more common driver in production simulations I would like to change the defaults.
Users who actually use PUGH and use its periodic boundary condition without setting the periodic parameters please speak up.
Ideally one would precede the change of defaults with an announcement to the mailing list and maybe even spread it over two ET releases.
It should be done though (and
#745 ought to be fixed). Otherwise other users might have to experience the joy of having to wait for a day for a test run on a busy cluster only to have it fail due to Carpet complaining about the periodic Parameters being set (since the debug executable had PUGH compiled in but the one to generate the checkpoints I was investigating had not). Fixing #745 would solve the problem of mysterious error messages aborting runs but would still leave two implementations with different default parameter values.