Re: Question about Request Sense case in scsi_lib.c

[James Bottomley <James.Bottomley@SteelEye.com>]

On Tue, 2004-10-12 at 11:59, Dave Olien wrote:
> Thanks for the feedback.  Yes, Automatic volume transfer is on, and I
> was expecting there'd be poor performance as a result.  I just
> didn't expect to get IO errors.  The odd thing is that the "bus reset"
> leads to the SCSI request being requeued.  But every once in a while,
> the requeue fails with errors and the request is failed.  I'll look at
> these cases a little more closely, try to understand why the requeues fail.

Hang on a minute ... if you're ping pong'ing the drives using AVT, those
transfers take time to achieve.  The device is probably returning UNIT
ATTENTION, NOT_READY while the transfer is in progress.  This is
probably the source of the requeue.

As for the error, I still don't understand that, but it looks like
something went wrong in setting up or tearing down the dma mapping, so
that it was incorrectly described when this happened a second time.

James