[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Frank Cox wrote:
On Mon, 31 Dec 2007 13:16:14 -0700
Phil Meyer <[email protected]> wrote:

If you are having students compile stuff, then you need to stick to the lowest common denominator (32bit) or else they cannot use those compiled programs elsewhere.
This is a bit of a niche issue, but it may be important with regard to certain
applications.

You can use DOSEMU (http://www.dosemu.org) to run old (and new) DOS programs on
Linux.  I wrote, support and maintain what has become a fair-sized suite of
special-purpose programs for a particular industry.  For various reasons, the
programs are written in PowerBASIC/DOS and run on Linux application servers
under DOSEMU.

Linux/x86_64 runs DOS programs under DOSEMU approximately 13 times slower than
they run on Linux/i386.  This is not as big of an issue as it may initially
appear, because even 13 times slower on a 3+GHZ computer is faster than
computers were running in back in the days when DOS was king of the hill. For
an interesting description of the reason this happens, I highly recommend
this article:
http://thebs413.blogspot.com/2005/10/what-is-x86-64-long-mode-memory-model.html
In short, running i386 Linux allows your CPU to use a “Virtual86” mode, while
x86_64 Linux requires that the whole thing be emulated in software which
obviously takes more horsepower and therefore runs more slowly
I have always assumed doesemu uses the 386's virtual-8086 mode, and 
that's not mentioned in Bryan J Smith's description above.




--

Cheers
John

-- spambait
[email protected]  [email protected]
-- Advice
http://webfoot.com/advice/email.top.php
http://www.catb.org/~esr/faqs/smart-questions.html
http://support.microsoft.com/kb/555375

You cannot reply off-list:-)


[Index of Archives]     [Current Fedora Users]     [Fedora Desktop]     [Fedora SELinux]     [Yosemite News]     [Yosemite Photos]     [KDE Users]     [Fedora Tools]     [Fedora Docs]
  Powered by Linux