Re: No SCSI Ultra 160 with Adaptec Controller

Matt Domsch (Matt_Domsch@dell.com)
Wed, 24 Jan 2001 14:27:08 -0600 (CST)


On Wed, 24 Jan 2001, Tom Sightler wrote:

> I temporarily disabled that code and the
> increase in IO's per second is measurable, though not earth shattering, but
> I was afraid to leave it that way because fast corrupted data is worth much
> less that only slightly slower good data.

I don't believe the problem is data corruption, but that there could be
some CRC data residual from an I/O which causes the driver to issue a
SCSI bus reset. As bus resets really kill performance, Doug thought it
better to slow the drive to 80 rather than run at 160 and have occasional
bus resets.

-- 
Matt Domsch
Dell Linux Systems Group
Linux OS Development
www.dell.com/linux

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