Subject: Re: SS2 and 2.0
To: Olev <hannula@gmail.com>
From: David Brownlee <abs@NetBSD.org>
List: port-sparc
Date: 10/26/2004 16:42:19
On Tue, 26 Oct 2004, Olev wrote:
> On Tue, 26 Oct 2004 01:54:40 -0600 (MDT), Rick Kelly
> <rmk@toad.rmkhome.com> wrote:
>> An SS2 with 128 megs is slower than 64 megs, since the memory card is sending
>> data over the sbus.
>
> And when that 64mb is full and your machine starts swapping? With less
> than 64mb of data it might be faster but the moment it starts swapping
> it gets many times slower.
An aside on this...
NetBSD supports the concept of different memory priorities,
so it would be simple to make the system prefer the fast
64MB over the slower 64MB. However the disk cache will use any
otherwised unused pages so normally it will reach a steady state
of complete memory anyway, which negates most of the gains in
the above. NetBSD has a unified buffer cache which excludes using
the slower memory for the buffer cache. You could create a ramdisk
on it and use it as the highest priority swap :)
--
David/absolute -- www.NetBSD.org: No hype required --