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Date: Fri, 6 Jun 1997 00:27:14 -0400
From: Charles Henrich <henrich@crh.cl.msu.edu>
To: "Jordan K. Hubbard" <jkh@time.cdrom.com>
Cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: Extremely poor interactive response under heave SCSI load
References: <19970605184813.26023@crh.cl.msu.edu> <17659.865556810@time.cdrom.com>
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On the subject of Re: Extremely poor interactive response under heave SCSI load, Jordan K. Hubbard stated:

> > Has anyone else noticed that a system with a large mount of unused (hence
> > dis
> k
> > cache) ram while under heavy SCSI load (or not so heavy really, e.g:
> 
> This has been a known bug for ages.  If you really want to test it out, try
> running mkisofs on a large image and then try to do something; I first
> encountered this back in FreeBSD 2.0 days. ;-)
> 
> I also doubt that the fix is trivial or John Dyson / David Greenman would
> have done something about it the first time I reported it back in December
> of 1994 (folks like Matt Dillon having also since reported on variations of
> it).

There has to be some solution, forcing the scsi command queue to search for
alternate commands every so often or something..  It just sucks :)

-Crh

       Charles Henrich     Michigan State University     henrich@msu.edu

                         http://pilot.msu.edu/~henrich