[Zope-dev] Granularity of Persistent Objects

[Paul Winkler]

On Thu, Jul 15, 2004 at 02:54:54PM -0400, Ian Beatty wrote:
> Greetings.
> 
> I'm developing a Zope (2.7) product, and I've got a particular
> persistent object that's going to be a real bottleneck, in that there
> will be many threads trying to change the state of the object more or
> less simultaneously. I'd like to "spread out" the problem by taking
> member fields of the object (lists, dictionaries, etc.) and making
> them persistent sub-objects in their own right. That way, changes made
> to one of them can be saved to the ZODB without causing thread
> conflicts with changes being made to others, removing at least some of
> the thred conflicts.

sounds reasonable...
 
> However, I don't know how to do this. Is it as simple as using a
> PersistentMapping where I'd normally use a standard Python dictionary?

Instead of PersistentMapping, see the various flavors of BTree,
e.g. OOBTree, IOBTree.  These do their own conflict resolution
and in your scenario that could be a big help.

-- 

Paul Winkler
http://www.slinkp.com