EDSI Problem

From: Chuck McManis <cmcmanis_at_mcmanis.com>
Date: Sat Jul 21 16:57:50 2001

At 03:56 PM 7/21/01 -0400, Jerome wrote:
[Large detailed description of anomalous behaviour]

Hi Jerome, have you tried moving your disk controllers closer to the
CPU? moving them up the bus grant chain will help. Also you can tell the
RQD11-EC to limit its DMA burst size which allows other boards to get in a
bus cycle when they need to. I had a problem where adding a SCSI controller
to a VAX killed disk performance on some ESDI drives but it was entirely
due to the SCSI controller doing large DMAs that interfered with the time
available for the ESDI drives to read or write buffers.

--Chuck
Received on Sat Jul 21 2001 - 16:57:50 BST