On Mon, Feb 28, 2011 at 5:09 PM, Maurits van Rees
> Op 28-02-11 16:34, Martijn Pieters schreef:
>> On Mon, Feb 28, 2011 at 16:22, Hanno Schlichting<ha...@hannosch.eu> wrote:
>>> Blobs are considered experimental in ZODB 3.8. Especially the entire
>>> blob cache changed completely for ZODB 3.9.
>>> I think you might want to upgrade to Plone 4 and ZODB 3.9 to get a
>>> stable environment. Or you'll likely run into more problems.
> Thanks for the advice, Hanno, also on the plone-dev list. This is the
> first time I have read such a clear warning against using blobs in Plone
> 3 though (same for Zope 2.10.x I guess).
> http://plone.org/products/plone.app.blob also gives no clear warning.
> What do others think?
To quote Jim: "I consider blob support in 3.8 to be somewhat experimental." 
You can use blobs in Plone 3 / ZODB 3.8. That's how we developed it
and then ironed out all the problems. But since we have more stable
versions of the software today, it doesn't make a lot of sense to go
back to the early development version. ZODB 3.9 has much more stable
blob support and direct support for RelStorage (without patches). If
you want to use either of those, you do yourself a favor by using the
latest stable versions.
For more information about ZODB, see the ZODB Wiki:
ZODB-Dev mailing list - ZODB-Dev@zope.org