> 2. It is way slower in file "copy/compare" than other DOSes.
>   (maybe we should make FAT and DIR data access smarter?)

depends on a couple of factors; the huge threat on 
http://www.drdosprojects.de/forum
about FreeDOS is slow was less then scientific

a) COPY
   FreeDOS allocates always the lowest unused cluster, even if
   the file should be enlarged by a large ( > 1 cluster) amount.
   this potentially searches a big part of the FAT to find place
   and writes the file fairly fragmented

   search for a bunch of clusters that are able to fit this request
   could accelerate this

   MSDOS 5 has been reported to allocate buffers on a 'round the disk'
   alghorithm (continue to search instead of restart from zero); has
   been reported to slow fragmentation
     
b) COMPARE
   if enough (small) files in large enough directories with enough
   directory depth are compared, it might matter that fastopen isn't
   implemented. Anybody ?


> I would like to comment on 1, please correct me if I am wrong...
>>>> Experts should be Bart, Arkady, Lucho and Tom :-). <<<

> - you can say "BUFFERS=-5" if you want "5 and not more than 5"
>   (as opposed to "BUFFERS=5" which is "at least 5" in FreeDOS)

> - HMA allocation (int 2f.4a0n) in FreeDOS should allow apps (such
>   as Jack's drivers) to use the free HMA space beyond the user-
>   selected BUFFERS. So even if we fill all space with extra buffers
>   while the space is unused, we free that space for more useful
>   things as soon as some app asks for it.

> Maybe there is a bug in int 2f.4a0n handling and/or config.c?

yes and no; see
http://www.bttr-software.de/forum/forum_entry.php?id=867


> - Arkady and Bart in 2004
> - Bart in 2001
> - Bart in 2004 (moved fnodes into HMA)
> - Lucho in 2004
> - Tom in 2001 (created inithma.c)
the HMA buffer logic came much later ;)



Mit freundlichen Grüßen/Kind regards
Tom Ehlert
+49-241-79886




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