[ZODB-Dev] Concurrent transactions

[Stefan H. Holek]

Counting in the ZODB is more or less a no-go. You will get write  
conflicts, and your ZODB will grow (too) quickly. That said, you may  
want to look at BTrees.Length for a "counter" with built-in conflict  
resolution.

Stefan


On 1. Jun 2007, at 09:47, Kai Diefenbach wrote:

> After reading some documentation about transactions, concurrency and
> atomicity, I don't think that the following issue is a problem, but  
> I'd
> be nice to get confirmation from some exports. Or - of course -  
> that it
> doesn't behave in the way I think.
>
> Within an adapter I increase a counter (e.g. for every download of an
> file) by doing:
>
>         self.counter[0] += 1
>
> self.counter is a PersistentList stored as annotation.
>
> Could there be a problem with concurrent access to the counter? With
> other words:

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