From owner-freebsd-scsi  Sun Nov 16 02:41:59 1997
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Date: Sun, 16 Nov 1997 02:41:41 -0800 (PST)
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To: gibbs@plutotech.com
CC: hbarker@rhiannon.sm.dsms.com, hackers@FreeBSD.ORG, scsi@FreeBSD.ORG,
        aic7xxx@FreeBSD.ORG
In-reply-to: <199711160511.WAA24691@pluto.plutotech.com> (gibbs@plutotech.com)
Subject: Re: AHC / SCSI UPDATE
From: asami@cs.berkeley.edu (Satoshi Asami)
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Justin:

 * Sorry for not responding sooner, but I don't read this list regularly
 * anymore...

Which list you are talking about?  (I hope that's not scsi! :)

 * Remeber that it's not really the type of device that matters, but the
 * possibility of starvation.  If you have lots of concurrent I/O going on
 * to multiple disks on a single chain, you can still experience this problem
 * (Hi Satoshi!).

Yeah, we've seen it too.  Lots of IBM DCHS drives on a couple of
chains, lots of random I/O, and sooner or later we'll get the "timed
out while idle" on one of the drives.  (And then that drive spins
down, which has been a headache for us for quite a while...however,
recently Justin & co. have given us patches to fix this and we're
testing it now.)

Satoshi