[ewg] APM Example

[Roland Dreier]

 > > You don't know the time that the transition occurred, except that it
 > > is between when you called modify QP and when it returned.  But an
 > > asynchronous event doesn't really help, does it?

 > It does help. APM is not only defined for network fault tolerance, it can
 > also be used for load-balancing. With this event, one can know when
 > the path is loaded and it is safe to call modify_qp.

I guess I don't really understand how you're using this event.  What
advantage is there in getting an async event at some unknown time
(maybe before the modify QP operation returns, maybe after)?  What
does it let you do that you can't do with the verbs architecture as
defined strictly by the verbs?

(I never believe in strictly following specs when they don't make
sense, but I also don't believe in adding non-standard features
without a compelling reason)

 - R.