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
> * 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
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