id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
10853	improve get_page_hierarchy	hailin		"current get_page_hierarchy has O(N*N) complexity. 
It is super slow when N is a few thousands.

We should improve this to O(N) using techniques similar to #10852. 
"	enhancement	closed	normal	3.0	Performance	2.8.4	normal	fixed	needs-unit-tests	m@… mike@…