Subject: Re: pciide performance on alpha
To: Jason Thorpe <>
From: Manuel Bouyer <>
List: port-alpha
Date: 08/12/1999 20:46:53
On Thu, Aug 12, 1999 at 09:59:31AM -0700, Jason Thorpe wrote:
> Note that the 164SX has a wimpy memory bus speed compared to the 164LX
> and the original PC164 (which had the best of all of them, actually).  This
> might contribute.
> If you get better transfer rates on the *same machine* under a different
> OS (as was implied earlier in the thread, I think), then there may be
> a problem with how we initialize the Cypress controller... but that
> would be the only issue; the vast majority of the PCI IDE code is
> shared between all controller types.

The problem here is that he is getting the same bad performances with a
Promise Ultra/33, where the same board with the same driver in a PC flies ...
Maybe there's a problem at a upper level (mainbus/pci bridge) ?
A lot of parameter seems uninitialised as well in the standart PCI header
(latency being one).

Manuel Bouyer, LIP6, Universite Paris VI.