From:	tyoung AT netaxis DOT com (tom young)
Subject:	Slooooww Iooooo -- Please help.
Newsgroups:	comp.os.msdos.djgpp
Summary:	Program runs ten times as fast under Linux as DOS
Keywords:	Linux dos-gcc MSDOS DJGPP Performance
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Date:	Fri, 02 Oct 1998 01:06:09 GMT
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

I am using dos-gcc on Linux to cross-compile my Roth IRA Calculator
program to MSDOS.   DJGPP is terrific, but for some reason the
program runs about ten times as fast under Linux as under DOSEMU
or Windows 95.  Am using gcc-2.7.2.3 and binutils-2.9.1.0.4.

GPROF on DOS shows:
		Each sample counts as 0.055556 seconds.
 	 %   cumulative   self              self     total
	 time   seconds   seconds    calls  Ts/call  Ts/call  name
	100.00      1.22     1.22                             __dpmi_int
			. . . 

so, is seems disk and screen IO is a problem, but what is the solution?
The program reads several small text files and printf's to the screen.
A typical run is .27 seconds elapsed under Linux and 3 seconds under
MSDOS.  Hundreds of runs will ultimately be required. 

I have RTFM to death.   Any ideas? 

	Tom 
 

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