Re: SCSI command order issue

[bberg@bswd.com (Brian A. Berg)]

SCSI supports Command Tagged Queueing, which allows more than 
one operation to be outstanding from an initiator.  The serial
number you mentioned could be the tag that is applied to outgoing
commands.  Assuming that both the initiator and target support and
use this feature, out-of-order responses may be received by an
initiator.
___________________________________________________________________
 Brian A. Berg            bberg@bswd.com        Voice: 408.741.5010
 Berg Software Design                             FAX: 408.741.5234
 P.O. Box 3488         visit the Storage Cornucopia at www.bswd.com
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> Hello,
>
> Here I ask one question about SCSI protocol.
>
> I traced the linux kernel source code about SCSI module.
>
> In SCSI module, every SCSI command block is assigned
> one unique serial number. However this number is only
> valid before the block is returned to the SCSI middle layer.
>
> There is no mechanism of sequence control for SCSI.
> What is your opinion about the SCSI block out of order
> when they return to upper layer ? What do your people
> think about this ?
>
> Thanks
>
> Wilson