Sender: fabrice AT asim DOT lip6 DOT fr
Message-ID: <34755A66.1845@trash.lip6.fr>
Date: Fri, 21 Nov 1997 10:54:46 +0100
From: Fabrice ILPONSE <fabrice AT asim DOT lip6 DOT fr>
MIME-Version: 1.0
To: djgpp users group <djgpp AT delorie DOT com>
Subject: DJGPP too slow!
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Hi!
Here's the topic back.

	That time have made a new test concerning video memory access.

	TEST: DISPLAY THE DATA SEGMENT/SELECTOR directly to the video memory
(BLIT) 32000 words.

	For comparison: BC 3.1 and DJGPP.

	Befor ALL: even in BC 3.1, i've used 32 bits inline assembly.
		   i haven't used any existing libraries!

	The  PROG:

		- switch to video mode 320x200x256
		- loop
			- change color 0 to red
			- BLIT
			- change color 0 to black
			- wait retical retrace

	I've got a 486 DX2 66.

	Results:
		- BC 16 bits red takes  40% of screen height
		- BC 32 bits 45 - 50%
		- DJGPP      90 - 95%

	Those values are approximated. (humain looking)

	I repeat it, i do not say anything about the djgpp generated code. I
think it's as good as the BC one. But what else can slow down the
performances?

	Protected mode perhaps!

	SOON: i'll  try to do the same under my modified protected mode BC 3.1
version.

Bye 
-- 
	^ ^ ^
	| | |
	+-+-+	Fabrice ILPONSE
	  |	<fabrice AT asim DOT lip6 DOT fr>
	  |
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	  -