Re: Food Tasting, Memory and Rolling Back Transactions.

Hi, Rick.

Ross Rick wrote:
> As I understand it, food tasting keeps a complete duplicate model set  
> in memory and runs the transaction against the duplicate first to  
> ensure that it is safe.
>
> 1.   Is that correct?
>   

That's my understanding.

> 2.   If it is correct then is it correct to presume that I can  
> effectively double the amount of memory available to storage by  
> turning it off.
>   

That is correct.
> 3.   If I turn it off, what are the ramifications?    It seems  
> possible that rolling back a transaction would then be my  
> responibility.   Is that correct?
>   

The risk is that a transaction blows up in the middle, leaving your 
model in an inconsistent state, one that might not be what you'd get 
from replaying the log. I think of that less as being responsible for 
rolling back, and more for being responsible that your transactions 
never, ever break. But perhaps it amounts to the same thing.

> Finally,  closing the Prevayler, this should release all memory, right?

Subject to all the joys of the JVM, that's my understanding. I haven't 
verified that myself, though, as my Prevayler instances tend to be 
long-lived.

William

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