Re: [MiNT] MiNTlibs question

[Thomas Binder <gryf@hrzpub.tu-darmstadt.de>]

Hi!

On Tue, Apr 27, 1999 at 04:03:52AM +0200, Guido Flohr wrote:
> Hm, is that unchangeable?

Well, for a stock Falcon or TT, it's no problem to create an MMU tree
from scratch with whatever page size you want. But for 040-equipped
machines, you have to use the existing MMU setup with as little changes
as possible, because Milan, Hades, Afterburner, and so on all have a
different layout of their physical memory. On some machines it's even
important that some descriptor addresses (for hardware emulation) remain
the same, so changing the pagesize is at least a PITA, if not impossible
for some machines.

OTOH, an MMU setup with 4k pages can easily be used for 8k-based memory
protection.

> Anyway, the
> page size will only become relevant when MiNT provides a virtual memory
> management.

No, the pagesize is already relevant for memory protection. Or were you
referring to something different here?

> So, all of you: Should I change the chunksize to 8k in malloc() then?

I would opt to, though I'm not familar with the internals, either. But I
can't imagine there are negative side effects if there's already a
possibility to change it. Also, losing half of the available block for
each call to Malloc() with active memory protection seems to be a much
more negative "side effect" of the default 4k.


Ciao

Thomas


-- 
Thomas Binder (Gryf @ IRCNet)  gryf@hrzpub.tu-darmstadt.de
PGP-key available on request!  binder@rbg.informatik.tu-darmstadt.de