[Zope-dev] ZODB and # of objects

[Michel Pelletier]

> -----Original Message-----
> From: Andrew M. Kuchling [mailto:akuchlin@mems-exchange.org]
> Sent: Monday, September 27, 1999 7:29 PM
> To: zope-dev@zope.org
> Subject: [Zope-dev] ZODB and # of objects
> 
> FileStorage's property of requiring memory proportional to the number
> of objects in the ZODB may be causing me problems.  I'm running into
> trouble with a ceiling of 150,000 items, but the memory usage becomes
> too high, 60 or 70 or 80Mb well before reaching that point.  I don't
> think the problem is a memory leak in my code, but perhaps I'm doing
> something wrong; has anyone stored that many items in a ZODB before?
> What was the memory usage like?

Are you using substransactions?  If you are using 2.0.x, then you might
not notice any improvement with sub-transactions because of a
deactivation bug that was fixed just after the release (sigh).  If you
use the CVS version and tune your cache agressively, you should be able
to keep the memory below a ceiling for any number of objects.

ZCatalog is pretty agressive about this, not only does it sub-transact
but it also kicks the cache with self._p_jar.cacheFullSweep(1).

>        (The largest number of objects stored in a Zope database would
> be an interesting bit of trivia.)

Theoretically, 2^64.

-Michel