[Zope] BoboPOS file locking

[Paul Everitt]

Gregory Trubetskoy wrote:
> Right now, if the database is locked by a process, no other process can
> (or should for fear of curruption) access it.

Correct.  I believe 1.10 actually does this correctly on Windows now.
 
> I was wondering if there is any progress on making BoboPOS databases
> accessible from multiple processes? Is anyone working on addressing this
> at all?

In fact there is a paper already written on this.  Unfortunatley the
link is currently broken...artifact of our ongoing move to a good ISP
(CodeIt).

Anyway, in October Jim Fulton released an alpha of the next generation
of the database.  This next version will gain concurrency by making each
request have its own copy of the transaction space (up to a limit).  It
will also allow storage in a relational database, thus providing an
object system spread across multiple processes and machines.  I believe
Jim might also provide multiple process support with just the filesystem
storage option, or perhaps use something like bsddb.

Fortunately the other half of concurrency -- the object publishing part
-- has been done now.

Jim was *scheduled* to get back to it this month but a customer project
pushed completion of Zope Classes ahead of the database work.  When the
database work is done, we'll have Zope 2.

--Paul