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Date: Thu, 10 Jul 1997 15:16:14 -0400 (EDT)
From: Thomas David Rivers <ponds!rivers@dg-rtp.dg.com>
Message-Id: <199707101916.PAA06181@lakes.water.net>
To: ponds!zeta.org.au!bde, ponds!i-Connect.Net!Shimon
Subject: pertinent to my "daily panics" (was Re: Clists limited to 1024 bytes?)
Cc: ponds!cisco.com!bmcgover, ponds!FreeBSD.ORG!hackers
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I just saw the following in mail from Simon Shapiro <dg-rtp!i-Connect.Net!Shimon@ponds.water.net>:
> 
> > >We experienced a lot of complex problems with SCSI transactions until we
> > >bumped the sio interrupt bufferto double its size.  While performance
> > (on 
> > >the sio ports - we use them only for PPP) did not drop visibly, the
> > strange
> > >incidence of dropping biodone() calls virtually stopped.
> > 
> > This probably just made a race less common.
> 
> It would be interesting to actually solve this mystery;  how does a buffer
> overflow in the sio (under PPP) cause biodone to lose a completion.
> We know, with very high degree of certainty, that we do not lose
> interrupts, nor miss a call to scsi_done (which calls biodone, somehow).
> It appears that from scsi_done() up things drop in this case.  Not every
> time.  Nasty...
> 
> Simon
> 

 This looks like it's in the area of my "daily panic" problem...
Especially the part about "from scsi_done() up things..."

 Has anything more happened along this issue?  Did anyone discover
anything?

	- Dave Rivers -