Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!IRO.UMontreal.CA!martin
From: martin@IRO.UMontreal.CA (Daniel Martin)
Newsgroups: comp.sys.amiga.tech
Subject: [-] CHIP RAM Speed Problems
Summary: Please explain decrease of speed..
Keywords: A3000, CHIP RAM, Dhrystones
Message-ID: <1990Oct9.042900.8479@IRO.UMontreal.CA>
Date: 9 Oct 90 04:29:00 GMT
Sender: news@IRO.UMontreal.CA
Reply-To: martin@IRO.UMontreal.CA (Daniel Martin)
Organization: Universite de Montreal
Lines: 19


   I tested the speed of an A3000/25 MHz + Aztec v3.6 with the dhrystone v2.1 
program.  I enclosed the dhrystone program test loop with a Forbid() - Permit()
pair.  The results, using a stopwacth, small code (16 bit ints) and using only
c.lib was around 6000 dhrystones (i.e 30000 loops in around 5 seconds).  I used
cache and burst for data and instruction (setcpu 1.6).

   When the program was run without fast ram available (say 800k CHIP, 3k FAST)
those numbers fell to around 1760 dhrystones, (i.e. 30000 loops in around 17
seconds).

   Why is there such a speed decrease (more than 3x)?


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