Subject: Complexity order of low VM
To: None <tech-kern@NetBSD.ORG>
From: Andrew Cagney <>
List: tech-kern
Date: 05/30/1995 11:18:08

Does any one have hard data on the relative frequencies of different
calls to the lower level VM code (for any given architecture)?

In particular I am interested in the relative frequency of the `operations':

	`load-page' (into vm-map)

	`unmap-range' (of addresses from a vm-map)

	`delete-vm-map' (and all loaded pages etc)

In the case of the latter two, typically, how big are the address ranges
and number of pages involved? (8k, 8mb?).

Why?  I'm trading off the time complexity of the latter two operations
against that of the first (load-page).  (vis O(1) & O(some N) vs all
O(log(some N))).  I'm just wondering if it is worth it.