[openib-general] MAD queuing model

[Hal Rosenstock]

On Wed, 2004-09-01 at 14:43, Sean Hefty wrote:
> On Wed, 01 Sep 2004 15:38:15 -0400
> Hal Rosenstock <halr at voltaire.com> wrote:
> 
> > If an RMPP send is n WRs, is there a way for the access layer to know
> > before posting whether all the WRs for this will fit ? If so, is this
> 
> 'n' may be smaller than the size of the QP.

Do you mean larger rather than smaller so they all wouldn't fit ?

> > "worth" the expense of this operation or should they just be posted
> > until not fitting and the rest deferred (and RMPP will do the correct
> > recovery either locally or remotely) ? (I obviously haven't thought this
> > through in detail yet...)
> 
> As long as we can come close to maintaining the data rate, 

Not sure how "fast" things will be.

> I'm not sure that defering the sends helps anything.  

Certainly not in the case you cite above where all the RMPP WRs won't
fit on the QP at one time.

> I think we want to try to keep the queue as full as possible when it's busy.

OK and the main issue is fairness.

-- Hal