Subject: Re: FW: 2 Problems
To: None <>
From: Anders Magnusson <>
List: port-i386
Date: 11/15/1998 23:16:59
> said:
> > We don't have a lot of spare processing power laying around to deal
> > with inefficiencies.  Based on the above, it seems that scrolling is
> > the greater of the two issues to be addressed.
> It was clearly for the i386. From what I've heart, indirect jumps
> are extremely expensive on the vax, so the weights might be a bit
> different.
Actually, what is expensive is _all_ subroutine calls (as done with calls).
Indirect calls is not so much more expensive than direct ones, at least
not on 11/780 where I did my performance tests.

The monochrome console now supported is totally dumb; just a bitmapped
display, so the only thing that can be done to speed it up is to do
something like only take all writes to a special buffer, and when 
there is no more to write everything is put out once. This would decrease 
the times the display must be scrolled one row. It would not be too
complex to do this, and something in this direction should be done
anyway. As it is right now virtual terminals are switched at interrupt
level and that's not good at all.

I don't think any of the above affects anything else than the MD code.

-- Ragge