[Zope-dev] Temp Folders and Transient Object Containers

[Chris McDonough]

> So, why is the default Transient Object Container put in a
Temporary Folder?
> If I want to use an application specific one that doesn't get lost
on
> restart, is it OK to put it into a normal persistent folder?

Yup.

The TOC is put into the temp folder mostly because:

1) Sessions are write-intensive and cause bloat on undoing storages
   like FileStorage.

2) Sessions are write-intensive and cause conflicts when accessed
   via a "normal" ZODB connection.  The temp folder is mounted into
   a database which has a special "low conflict" connection type
   that ignores read conflict errors.

You will get more conflicts and more bloat if you put a TOC into a
normal persistent folder (esp. one backed by FileStorage), but it
will work.  That said, there are a few bugs in the 2.5 "transience"
implementation that I'm working on as we speak that might be more
egregious if you have a truly persistent TOC, so pls. keep an eye
towards 2.6 (or CVS ;-) in the next few weeks.  You will notice the
bugs in the form of phantom key errors (not unlike the old Catalog
bugs ;-)

- C