Hi Shannon,

Good question. I haven't really considered an app initiating this but I
think that could work.

The ultimate use case for this, in my mind, is to eventually support
transitioning http sessions from a blue app to a green app in a blue/green
deploy type of scenario.

I think this could be done with the a combination of a sticky app feature
and the request weight load feature you mentioned in your talk.

With those 2 features I could write my application to indicate to the
router that I wish to maintain sticky app. Then I could set request weight
to some percent (possibly even 100%) of load to the new app. That way
users would eventually and smoothly transition all new http sessions to the
new app.

So, to answer your question I think it quite reasonable to ask the
application itself, through cookie or something, to declare if it wants
instance, app, or no stickiness. However, I believe the mechanism to
declare how much load each app bound to a route should get would need to be
controlled outside the app, but, could potentially be the very same
mechanism you envisioned for the upcoming load weight feature.

Does that make sense?

Mike