On Wednesday 30 October 2002 2:00 pm, Chris Withers wrote:

>  Hmmm, I'm actually using the Alpha here, did you fix it up after that?

no. Ill spam you off-list about this.

>  > A malicious script? yes.  I think this is a bogus argument for a change
>  > to ZODB; a malicious script could also bring the server down by creating
>  > large numbers of non-persistent objects
> 
>  Not malicious, consider this:
> 
>  for brain in context.some_catalog(an_index='fish'):
>     object = brain.getObject()
>     object.doSomeMaintenence()
> 
>  ...now if an_index goes walkies, you've just loaded all the obejcts you've
>  cataloged into memory by mistake.

Yes. IMO this script *needs*:

1. either batching, as is traditional for a search results page. The search 
might be huge, but memory useage will be controlled if the batch size is 
reasonable:

2. or a garbage collection tickler as part of the loop. See ZCatalog's 
"reindex all" implementation for an example.

>  Can you do either of those from Script (Python)'s?

Probably not, but I dont do much ttw work.

>  > The problem is not the hardness of the limit, but rather that the limit
>  > is applied at the right time. Any automatic enforcement mid-transaction
>  > is liable to cause problems (for example, think about _v_ attributes)
> 
>  how would raising a MemoryError (as happens when you run of RAM for real)
>  affect these?

Not a bad idea. This could be done easily and efficiently in Connection.py

Of course it still doesnt help with the case of memory usage by non-persistent 
objects.

>  > I can suggest a change to your indexing loop that will make this happen
>  > automatically. Would that help? ; -)
> 
>  What would the change be?

sys.exit(1)

;-)



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