FAQ

Kirk Wood cpt.kirk at 1tree.net
Thu Jun 21 14:50:44 EDT 2001


On Fri, 22 Jun 2001, Shaun Oliver wrote:
> I agree with that also. windows9x don't use dynamic memory
> allocation. this means that the stack is prone to becoming fragmented. and
> that is why windblows9x falles over more often than it's nt counterpart.
> all breeds of unix and windows nt/2000 all use dynamic memory allocation
> so as to give us the advantage of longer uptime. and a less fragmented
> stack, thus fewer crashes or lockups.

Actually this gets more blame then is reality. The simple fact is that the
memory fragmentation is not a large factor. What is a major factor is that
all Win9x versions (including ME) include a large sum of code from
win3x. This code is included for either of two reasons. The first was
speed and the second was backward compatibility. The later is te main
reason for 3x code appearing in ME.

The fact is that 95 had about a third of its code written in 16 bit
code. This was for compatibity and speed. When they released 98, the share
dropped to about 25%. All indications were that ME would retain a good
chunk of the 16 bit code though it would be re-written.

In all of the versions of winblows not in the NT line programs could
communicate through shared memory. This set the system up for memory
leaks. As if a program allocated memory then failed to release said memory
it was out of service until the next reboot. This was done because there
was no way to know what memory was being shared and the OS recovering the
memory lead to spectacular crashes.

WinNT took a different approach to this. In the ealy versions of NT, the
memory was duplicated to different programs. This worked fine as long as
you didn't run too many 16 bit programs. Then in version 4, they decided
to put all 16 bit programs into seperate memory space. This gave good
performance and yet protected all but other 16 bit programs from their
memory overwriting ways.

I know this is more then most want to know. But if you are going to talk
about the failings of a company bent on domination at least get it right.

=======
Kirk Wood
Cpt.Kirk at 1tree.net

Nothing is hard if you know the answer or are used to doing it.





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