Date: Fri, 10 Sep 1999 19:38:47 -0600 From: "Justin T. Gibbs" <gibbs@caspian.plutotech.com> Cc: Andrew Gallatin <gallatin@cs.duke.edu>, "Justin T. Gibbs" <gibbs@plutotech.com>, scsi@freebsd.org, gibbs@freebsd.org, anderson@cs.duke.edu Subject: Re: data corruption when using aic7890 Message-ID: <199909110138.TAA03862@caspian.plutotech.com> In-Reply-To: Your message of "Fri, 10 Sep 1999 16:36:35 MDT."
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>I would continue to tweak the variable. I assume you tried setting >the read threshold to MIN and the write threshold to MAX? In other >words, don't start a read from host memory until the FIFO is almost >empty, and don't start a write to host memory until the FIFO is almost >full. The assumption here is that PCI is faster than the SCSI bus >speed so we'll get the longest bursts this way. I misread the data book. If you set them both to MAX, then you would get this behavior. The read fifo threshold is based on the amount of empty space in the fifo, not the amount of data in it. -- Justin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message
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