Re: Multitasking during disc access (was: Re: MiNT scheduling)

[Jo Even Skarstein <joska@nuts.edu>]

On Thu, 13 Nov 1997, Konrad Kokoszkiewicz wrote:

> > Adding the "SLICES=1" line to mint.cnf seems to have completely fixed the
> > problem.
> 
> That's pretty interesting, cause the difference between SLICES=1 (as you
> have set) and SLICES=4 should be hardly noticeable for humans. Afaik,
> one slice is 1/200 secs...

Well, it does. Try experimenting with different values and you'll se
what I mean!

> > Now if only somehow MiNT could multitask while disc access is occuring. Is
> 
> That depends. I have IDE disks only, so any disk access is blocking. But I
> hear that SCSI disk access isn't blocking, MiNT works "smoothly". Of
> course, its for Falcon, where SCSI is DMA...

SCSI is DMA-based on all TOS-boxes I know of (except the Hades, and
perhaps Milan), but it doesn't help MiNT much: The various functions
you hook into the kernel via the XFS/XDD-interface doesn't return
until they've done their stuff (e.g. read/written some stuff), and
AFAIK they do it in supervisor-mode. And all (x)bios-functions runs in
supervisor-mode for sure, so even changing MiNT won't work without
rewriting the (x)bios... 

We'd better wait for Fenix, or start porting MiNT-stuff to MagiC ;-)


/*
** Jo Even Skarstein    http://www.stud.ntnu.no/~josk/
**
**    beer - maria mckee - atari falcon - babylon 5
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