[ZODB-Dev] Data.fs size grows non-stop

Christian Theune ct at gocept.com
Mon Dec 7 11:35:21 EST 2009

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 

Christian Theune · ct at 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

More information about the ZODB-Dev mailing list