[ZODB-Dev] 3.8.1b8 released and would like to release 3.8.1 soon

[Hanno Schlichting]

Dieter Maurer wrote:
> Wichert Akkerman wrote at 2008-9-24 09:44 +0200:
>> Jim Fulton wrote:
>>> I'd appreciate it if people would try it out soon.
>>>    
>> I can say that the combination of 3.8.1b8 and Dieter's 
>> zodb-cache-size-bytes patch does not seem to work. With 
>> zodb-cache-size-bytes set to 1 gigabyte on an instance with a single 
>> thread and using RelStorage Zope capped its memory usage at 200mb.
> 
> I can see two potential reasons (beside a bug in my implementation):
> 
>  *  you have not used a very large object count.
> 
>     The most tight restriction (count or size) restricts what can be
>     in the cache. With a small object count, this will be tighter than
>     the byte size restriction.

The object count is 650000. Without the cache-size-bytes setting this
produces a memory load of about one gigabyte to one and a half gigabytes
currently.

>  *  Size is only estimated -- not exact.
> 
>     The pickle size is used as size approximation.
> 
>     I would be surprized however, when the pickle size would be five times
>     larger than the real size.

IIRC turned into a packed Data.fs the size of the whole content is about
25 gigabytes of all typical Plone content.

I think a possible interaction with RelStorage (which we asked Shane to
look into) or Jim's mentioned cPersistence.h change was far more likely
causing this.

Hanno