[rescue] 128 bits...

[Lionel Peterson]

--- "Jonathan C. Patschke" <jp at celestrion.net> wrote:
> On Fri, 7 Feb 2003, Dave McGuire wrote:
> 
> > > a bit huge... I am fascinated by the idea of a CPU that addresses
> > > directly into secondary storage, data files exists as address
> > > locations, not inodes or sectors/tracks/platters on a SCSI ID...
> >
> >    George Adkins and I were discussing something along these lines
> > a few months ago.  An architecture like that has some interesting
> > possibilities.
> 
> And interesting problems.  I suspect you'd want object like that
> aligned at certainly memory addresses (segments, if you will), sort
> of like how IP networks are aligned at the all-zeros address of a
> certain mask.

I don't follow this, but it's probably just me...

> With many of these interesting memory-mapped objects, you'd quickly
> exhaust the address space (Assuming a maximum filesize of 4GB, you
> could have no more than billion files, assuming a larger filesize
> decreases the address space exponentially).

You would consume the address space in a linear fashion, not
exponential they way I envision it...
 
> The alternative would to have a gigantic lookup table, which would
> consume space in itself, and bring with it all the problems of
> directory management (fragmentation, etc.).

You don;t solve real-world problems by using this type of storage
arrangement, you solve programming/logical problems...
 
> You could, I suppose, virtually map things at nice offsets, and
> physically map them against a table (a la TLB), but you'd still have
> to do a lot of song-and-dance behind the scenes.

Naw, the OS would. ;^)

The fundamental invention in Unix was the decision that "everything is
a file" - mapping storage to a linear address space is really taking
this original idea to the next logical level. If you can tollerate a
segmented address space, the possibilities are *huge*...

=====
Lionel

"Nothing would please me more than being able to hire ten
programmers and deluge the hobby market with good software"
Bill Gates, in "An OpenLetter to Hobbyists" dated February 3, 1976
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