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From: Terry Lambert <terry@lambert.org>
Message-Id: <199604302033.NAA07754@phaeton.artisoft.com>
Subject: Re: lmbench IDE anomaly
To: msmith@atrad.adelaide.edu.au (Michael Smith)
Date: Tue, 30 Apr 1996 13:33:20 -0700 (MST)
Cc: koshy@india.hp.com, hackers@FreeBSD.ORG, current@FreeBSD.ORG
In-Reply-To: <199604301324.WAA21150@genesis.atrad.adelaide.edu.au> from "Michael Smith" at Apr 30, 96 10:54:18 pm
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> That's about right.  The SCSI disk gets the chance to sort the I/O to suit
> itself, optimising its performance.  The IDE disk only gets to look at one
> transaction at a time, so it's at the mercy of the disksorting code in
> the operating system.  I don't know that FreeBSD's disksort stuff is 
> terribly wonderful, but I'd happily stand corrected.

The disksort stuff is pessimal.  Contact mday@elbereth.org for details.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.