On 12/07/2009 05:00 PM, Alan Runyan wrote: >> I'd just like to add that there's some changes that can be related to this: >> >> - we had some classes inheriting from Persistent that now inherit from >> something else as well (but no extra arguments are being added, AFAIK); >> - we added some zope.interface definitions to some Persistent classes; >> >> maybe this causes some kind of behavior that we were not aware of? > > I doubt it. Thousnads of people are doing this and do not report the same > behavior. > > What is more likely is that a programmer is changing a persistent object > very often. One of the downsides of the ZODB is that it is so transparent > it is possible to unwillingly make database changes. > > A design pattern for RDBMS is to have 2 pools. READ pool and WRITE pool. > Often the READ pool comes from some replica and WRITE is to the master. > I'm unsure this pattern would work for ZODB. I know Malthe was thinking > about this but unsure if he had anything concrete.
My guess: have a ZEO fan-out setup and configure the read pool ZEO servers as read-only. Any transactions writing will fail miserably right away. -- Christian Theune · c...@gocept.com gocept gmbh & co. kg · forsterstraße 29 · 06112 halle (saale) · germany http://gocept.com · tel +49 345 1229889 0 · fax +49 345 1229889 1 Zope and Plone consulting and development _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev