This question is not directed at Chris, but rather someone who might answer the question.
But why would Amiga need a constant time memory allocator? Amiga is not an RTOS... I guess, the side effect here, is not so much that its a constant time allocator, but that it tends to work better in some other fashion...i.e. the old allocator became fragmented to the point of being unusable?
While I appreciate a one-off patch aimed at fixing one of the deficencies in Amiga OS...this sort of thing, shows how not having a real Amiga, Inc. really hurts this community...such patches need to be part of OS releases.
Sadly, I understand OS releases aren't to be had anymore :-(