Tagged Queueing and Dque Bit
Klaus.Steinberger at Physik.Uni-Muenchen.DE
Tue Jan 6 03:24:02 PST 1998
I have now some boxes running Linux 2.0.33 (aic driver version 4.1.1/3.2.1).
I now have tagged queueing enabled as suggested and it works rock solid.
But with one box it didn't work, until I figured out that the drive
claims to have tagged queueing, but has the Dque bit set to one
in the control mode page (Dque inhibits tagged queueing).
The driver did time outs and gave me error messages that there is no
active SCB for this drive.
Host: scsi0 Channel: 00 Id: 01 Lun: 00
Vendor: SGI Model: IBMDSAS-3540 Rev: S47K
Type: Direct-Access ANSI SCSI revision: 02
After I figured out the Dque bit, and reset it to zero, it worked flawlessly
with tagged queueing enabled.
So I would suggest, that the driver should check also the Control Mode
Page (if available), and should honor the Dque bit (fall back to not use
tagged queueing if Dque is set).
Klaus Steinberger Beschleunigerlabor der TU und LMU Muenchen
Phone: (+49 89)289 14287 Hochschulgelaende, D-85748 Garching, Germany
FAX: (+49 89)289 14280 EMail: Klaus.Steinberger at Physik.Uni-Muenchen.DE
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Size: 290 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/aic7xxx/attachments/19980106/cb18f243/attachment.bin
More information about the aic7xxx