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

[Christian Theune]

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 · ct at gocept.com
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