[Developers] Recover SaveAndRestore variables with PUGH

[Ian Hawke]

On Wed, 2006-10-18 at 19:43 -0500, Erik Schnetter wrote:
> On Oct 18, 2006, at 03:02:02, Luca Baiotti wrote:

> I think the root of the problem is that evolution_method="none" does  
> not do anything to time levels.  It should instead copy the previous  
> time level into the current time level in the prestep bin.  The  
> current mechanism was implemented when people would use only a single  
> time level with stationary spacetimes; only with Carpet do people  
> want multiple time levels in that case, which breaks things.
> 
> Ian, do you think that this would also solve the problem?

It would work, and is rather more satisfactory than modifying MoL (as
SaveAndRestore variables just mean "these might be evolved by some other
thorn"). 

I still believe that the only guaranteed way of ensuring consistency
after recovery is to checkpoint all timelevels, even with PUGH, because
you never know what somebody's going to try and do.

Ian