Never Use Temp ZODB Folder Across Multiple Requests
Storing into temp folder is incompatible with ZEO and clustering, unless this is
only for a single transaction. If you need to share data over multiple transactions,
either user ERP5 preferences, an ERP5 selection object or any ad hoc storage. ERP5
selection object implementation is worth having a look at because it has been
implemented to reduce ZODB conflicts by hashing selections per use. Make sure
though that all changes to ZODB storage happen within the same mounting point
of ZODB (ex. /erp5/portal_selections). This allows for selective compacting ZODB
from time to time or for using different ZODB backends whenever complete history
and traceability is not needed.