#5 Performance Enhancement

[Vincent Sheffer]

JOB currently caches DataShell objects. Anytime a
Persist object is needed it is created and the correct
DataShell resulting in excessive objects being created.
Should actually cache Persist objects. The cleanest
way to do would be to just cache the Persist objects.
That solution may be prove to be the more complicated
to implement however. A simpler solution would be to
just have another cache of persist objects.