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From: lphillips@lpami.wimsey.bc.ca (Larry Phillips)
Newsgroups: comp.sys.amiga
Subject: Re: Amiga competitiveness
Message-ID: <2070@lpami.wimsey.bc.ca>
Date: 2 Oct 90 12:58:29 GMT
Lines: 40
Return-Path: <lpami!lphillips>
To: van-bc!rnews

In <14821@cbmvax.commodore.com>, daveh@cbmvax.commodore.com (Dave Haynie) writes:
>In article <420@caslon.cs.arizona.edu> cjeffery@cs.arizona.edu (Clinton Jeffery) writes:
>
>>Example #2: an Amiga's hard disk, even with FFS, is *ridiculously* slow
>>	compared to the _identical_ hard disk running DOS or UNIX/386.  This
>>	is based on empirical observation doing heavy C compiles on a 2000
>>	with 1MB ram and a 40 Meg ST-251-1.  Sorry.  I wish it were untrue.
>
>You obviously have something wrong with your hard disk setup.  Ok, well, some
>people would say that a 40 Meg ST-251-1 IS something wrong in the first place,
>but I won't go picking on Segate again.  And I doubt you'll find too many 
>identical '386 setups to compare it too; the number of '386 systems running
>SCSI or ST-506 is just slightly larger than the number of Amigas running
>EDSI (eg, 0).  ST-506 and EDSI have problems of interleave setup, not usually
>a problem with SCSI, that result in factor of 10 or more preformance changes.

Gee... I'm running an ESDI drive. Of course I have it hanging off a SCSI<->ESDI
adapter. It's pretty fast.. a LOT faster than any ST506 I have run either off
the 2090 or off a SCSI<->ST506 adapter (may have been partially due to the
adapter being a cheapo Adaptec 4000). The ESDI drive gets about 700KBytes/sec
on the 3000, using an Emulex MD-21 controller.

> It's impossible to know just what you have working against you.  Could be the
> disk interleave.  Could be it's not really formatted FFS.  Could be ...

Boy are you right on with that! The smallest things, set up poorly, can make
the difference between a 200KBytes/sec and an 800KBytes/sec transfer rate.
Happens all the time, and we see a lot of griping about slow disks because of
it.

-larry

--
It is not possible to both understand and appreciate Intel CPUs.
    -D.Wolfskill
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|   //   Larry Phillips                                                 |
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