2940 and 75MHz CPU clock

[Brian]

On Thu, 4 Sep 1997, Hansel Kwok wrote:

> Hi there,
> 
> Has anyone on this list been able to get the
> 2940 SCSI controller to work with a 75MHz CPU clock?
> 
> The controller always hangs when there is heavy
> disk access. I tried many things and is still
> unable to resolve the problem.
> 
> I tried that abort/reset patch, which reset the
> controller alright, but this is very annonying 
> as it resets very, very often.
> 
> Any help would be appreciated.

We tried everything we could with the 2940UW and Linux and Pentium 200mhz
chips.  Nothing.  We tried the latest patches, turning off optimizations
etc.  It seems under high disk load is when its most problematic.  We were
trying to do 2 controllers, and a total of 10 wide scsi devices.

After 2 weeks of trying everything, including forced perfect termination,
custom made top of the line SCSI cables made to exact lengths, etc.  We
could not stop the problems.

2 days ago, I installed a DPT3334 RAID controller and have had 0 problems.
Load average stays well below 1, while with the dual 2940UW's it sat at
about 2-3.

This is on a news server.


> 
> Thanks.
> 
> Hansel
> 

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