From: Brian S. Julin <bri@tull.umassp.edu>
  To  : Michael Gersten <michael@stb.info.com>
  Date: Wed, 18 Aug 1999 15:06:13 -0400 (EDT)

VC Switching

On Tue, 17 Aug 1999, Michael Gersten wrote:
> Lets face it: We want Linux, and the graphic console system, to
> run equally well on 1-4 MB cards on 386/486 systems, or 56 MB cards
> on P2's and P3's with 32-128 MB of memory, right?

I for one don't buy the "56M card" rational for killing VC switching
while in graphics mode.  Most apps won't use nearly that much of
the card's RAM.  In fact, a 56M card whose driver could protect it's 
memory area would allow us to stow away several VC's worth of fb
data *in video RAM* simultaneously; perhaps even to allow drawing
by several apps on their fb data whether or not their VC is 
focused.  Maybe even eventually allowing card<->disk DMA transfer
directly into the swap partition as needed -- who knows.

The only rational I see for it, and this one I *do* buy, is 
that switching makes things complicated and it's better to
get everything else (drivers, KGI, extensions) up to speed,
and get any concessions we can out of Linus to make fbcon 
useful, one by painful one, before tackling the vc-switching 
issue.

> Isn't it safe to assume that if someone puts a 56 MB video card
> into a machine, that that machine isn't a tiny underpowered box?

Nope :).  

But, you have good arguments in favor of a sane vc-switching system.
They seem to reinforce the point that the graphics card needs
to be viewed as a resource server, serving up frames, sprites, 
textures, and whatnot, and not seen as a single resource; except for 
the actual focus (of which there is only one per monitor attached 
to the card, so those are single resources.)

We should do the vc-switching system *right* even if it means
hacking it out entirely and putting it off for a while.

--
Brian S. Julin