Here's a quick comparison:


On Ultrix 4.2a on a 5k/200, without extraneous drivers, 32 Mbytes real memory,
and with AFS client software:

    % size /vmunix
    text    data    bss     dec     hex
    1330624 161056  1021776 2513456 265a30

    (output from top)
    Memory: Real: 7316K/19M act/tot  Virtual: 12M/34M act/tot  Free: 2308K

On NetBSD-current (with a GENERIC-like config), 64 Mbytes real memory:
    > size /netbsd
    text    data    bss     dec     hex
    853024  41776   91808   986608  f0df0

    (output from top)
    Memory: 4404K Act 9536K Inact 7788K Wired 40M Free 

Ultrix (and AFS) is consuming about 10 Mbytes.  NetBSD is consuming
about 7.5. There's a difference but it's not *that* great. It'd
be, roughly, 10% to 20% difference on a 16Mbyte machine, depending
on how the buffer cache scales.

(I don't know off-hand how many users, or how big a buffer cache,
 each system is configured for.)