Ordered Task Tags
dap at cisco.com
Fri Jan 26 16:44:58 PST 2001
* From the T10 Reflector (t10 at t10.org), posted by:
* "David Peterson" <dap at cisco.com>
The first paragraph you specify says it all:
"The rules for task set management apply only after the task is entered into
the task set."
This is why it is critical to ensure ordering (within the transport) for any
commands that must be executed in the same order as sent from the initiator.
The SAM-2 CRN is one mechanism to ensure ordering. Issueing a single command
and waiting for the status is another.
Take a look at SAM-2 clause 4.6.2 also regarding request/response ordering.
> -----Original Message-----
> From: owner-t10 at t10.org [mailto:owner-t10 at t10.org]On Behalf Of Santosh
> Sent: Friday, January 26, 2001 4:48 PM
> To: T10 Reflector
> Subject: Ordered Task Tags
> I have a question regarding Ordered Task Tags.
> SAM-2 Section 7 states :
> "The rules for task set management apply only after the task is
> entered into the task set."
> Further, the description of Ordered Task Tag (Section 7.5.2) states :
> "The Ordered Task Tag shall not enter the enabled state until all
> older tasks in the task set have ended."
> Based on the above, one infers that the enforcement of ordering
> is only w.r.t the order of tasks received at the target and is not
> w.r.t the order in which they were initiated.
> IOW, do the semantics of Ordered Task Tag imply end-to-end
> ordering from initiator to target, or only ordering w.r.t the
> tasks that are received into the task set at the target ?
* For T10 Reflector information, send a message with
* 'info t10' (no quotes) in the message body to majordomo at t10.org
More information about the T10