Rules governing stack purging

Mark Schonewille m.schonewille at
Mon Oct 30 12:26:51 EST 2006

Hi Richard,

It seems to be correct to assume that getting a property from a stack  
whose destroystack property has been set to true does not cause that  
stack to stay in memory. I tried the following in the message box:

answer file ""; get the bla of stack it; put the openstacks

and the selected stack file is not among the lines of the openstacks.  
(Dave, I think your reply in this matter is not correct, unless I  
overlook something).

If you delete a stack, you completely remove it from memory. If the  
stack happens to be a substack of a mainstack, that substack is also  
deleted. This means that you can only safely delete mainstacks.

As far as I know, you cannot purge a substack without either purging  
the mainstack or actually deleting the substack.




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Op 30-okt-2006, om 17:48 heeft Richard Gaskin het volgende geschreven:

> I'm working with a client on a system that makes extensive use of  
> data stored in custom properties.
> I had been under the impression that as long as the stack  
> containing the data has its destroyStack set to true, and as long  
> as we don't open the stack, everytime we access its properties  
> we're getting it fresh from disk rather than from cached memory.
> Is that correct?
> We're in the process of pinning down some anomalies in our system  
> which would seem to suggest that accessing properties can cause a  
> stack to remain in memory such that subsequent accesses are  
> obtained from memory rather than from disk.
> I would love to be wrong, as it would complicate our system to have  
> to manually purge each stack before accessing it.
> And as for that purging, in the absence of a purge command there is  
> the workaround of using the delete command, but at the moment my  
> memory's flakey:  does using "delete stack" merely purge the stack  
> but not delete the actual stack if it's a mainStack, or if it's a  
> substack?
> And once we confirm which type of stack we can safely purge without  
> deleting it using the "delete stack" command, what method do we use  
> to purge stacks of the other kind?
> -- 
>  Richard Gaskin
>  Fourth World Media Corporation

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