[DGD] Object upgrading

[Raymond Jennings]

Recently I made an update to kotaka, that atomically touches all
clones of an object with patchable programs in its inheritance tree.

However, I also have been running stress tests of instances with
object counts numbering in the multi-millions.

What's the best way to make sure all objects get upgraded?

Right now, I have a tight loop in ObjectD that atomically calls
call_touch on all clones of a patchable object, and then leaves a
background callout in PatchD to eventually nudge them all.

Is this the best way to do it?