Path: utzoo!attcan!uunet!crdgw1!vdsvax!trub!perley
From: perley@trub.crd.ge.com (Donald P Perley)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Performance Rating w/ A2091 and Quantum ProDrive 40S
Message-ID: <11522@vdsvax.crd.ge.com>
Date: 28 Feb 90 15:51:29 GMT
References: <1168@lpami.wimsey.bc.ca>
Sender: news@vdsvax.crd.ge.com
Reply-To: perley@trub.crd.ge.com (Donald P Perley)
Organization: GE Corp. R & D, Schenectady, NY 12345
Lines: 25

In article <1168@lpami.wimsey.bc.ca> lphillips@lpami.wimsey.bc.ca (Larry Phillips) writes:
>In <21294@watdragon.waterloo.edu>, mwandel@tiger.waterloo.edu (Markus Wandel) writes:
>>I've also found that a 68000 based Amiga doesn't really need more than 300K/sec
>>disk transfer rate.  My (homemade) interface goes that fast, and I've found
>>that all my compiles, Zoo compresses, etc. are now compute bound as shown by
>>the low duty cycle of the "blips" of the disk activity light.  And my
>>interface isn't even DMA.  So don't worry about it...

Well.... One of the advantages of a DMA interface is that is doesn't load
down the CPU as much so compress, etc would be able to run faster, and 
a higher transfer rate would be useful.  

I think loading programs, iff files, etc and opening drawers (if using
workbench) make up most of the "feel" of how fast a disk operates, and
they aren't especially CPU intensive operations. 

The original poster was unclear whether he was more concerned with 
transfer speed or the other stuff like directory scanning, file creation etc.
He also didn't say whether his friend with the 2090 (which he said was faster
than his 2091) has fast memory.  That could make a difference in performance,
as would the "addbuffer" count.


-don perley
perley@trub.crd.ge.com