Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!rutgers!cbmvax!jesup
From: jesup@cbmvax.commodore.com (Randell Jesup)
Newsgroups: comp.sys.amiga
Subject: Re: Benchmark:A3000 w/ AMAXII
Message-ID: <15090@cbmvax.commodore.com>
Date: 11 Oct 90 17:50:42 GMT
References: <1990Oct9.184447.4539@ee.rochester.edu> <15009@cbmvax.commodore.com> <28676@pasteur.Berkeley.EDU> <15070@cbmvax.commodore.com>
Reply-To: jesup@cbmvax.commodore.com (Randell Jesup)
Organization: Commodore, West Chester, PA
Lines: 31

In article <15070@cbmvax.commodore.com> martin@cbmvax.commodore.com (Martin Hunt) writes:
>>>In article <1990Oct9.184447.4539@ee.rochester.edu> tombs@ee.rochester.edu writes:
>>>>	A3000/25/50		MacIIci		MacIIcx			MAC+
>>>>Dhrys/sec 2871(2717)			3736(3816)	(768.8)
>> 
>>>The Dhrystone test doesn't use any floating point.  But the results do say
>>>a few things.  First, that AMAX seems to be taking on a bit more overhead
>>>than I would have expected.

>Fast RAM is used BEFORE Chip RAM, so the problem is most likely that
>something is using up all the Fast RAM.  In the case of a stock 2M
>3000, that something is the 2.0 OS.  Because ROMs are not out yet, the
>ROM image is loaded off disk, using up 512K of your 1M fast RAM.  With
>other OS processes using up fast RAM, you are lucky if you have a useful
>amount when you are finished booting. This is a very common cause of
>slow benchmarks on 3000s.

	Also, Amax may not be able to use memory above the 16M boundary,
since Mac programs (and maybe the OS as well) have in the past tended to
use the top byte for flag information, etc.  Only recently has there been a
push towards "32-bit-clean" programming there.  Martin is correct that if
it's a 1M fast/1M chip machine, it may not have a lot of fast memory left
for amax under the current MMU rom-images.  With real roms there will be
another 512K of fast ram available (at least under 2.0).

	The A3000 fastmem is in the 0x07xxxxxx range.

-- 
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.cbm.commodore.com  BIX: rjesup  
Common phrase heard at Amiga Devcon '89: "It's in there!"