Date: Mon, 15 Jan 1996 08:46:52 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Laszlo Vecsey <master AT micro DOT internexus DOT net>
Cc: djgpp AT delorie DOT com
Subject: Re: DJGPP (MSDOS/QEMM/WIN95) -> SLOW!


On 13 Jan 1996, Laszlo Vecsey wrote:

> I compiled a program under Turbo C++ 16bit which used lots of
> unsigned long multiplications and such, and was very pleased
> when it ran twice as fast (I did some time trials) when compiled
> with DJGPP. Running under QEMM however I found it was a bit slow,
> and it performed a little better from a Win95 shell. But when I
> compiled the same program on a Linux box, it went twice as fast
> yet again! Same processor (pentium 100) on both systems...

There is Chapter 14 in the DJGPP FAQ list (available as faq102.zip from 
the same place you get DJGPP) which deals with these issues; please read 
it and see if some ideas there help you understand the reasons for the 
above behavior.  Profiling your program to see where it spends most of 
the time might be useful here.

If nothing in the FAQ seems to help, please post more details about your 
program (in the spirit of that chapter in the FAQ), and someone might 
have the answer for you.