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From Dascalita Dragos <ddrag...@gmail.com>
Subject Re: Improving support for UI driven use cases
Date Sun, 02 Jul 2017 06:32:13 GMT
>  I think the opportunities for packing computation at finer granularity
will be there. In your approach you're tending, it seems, toward taking
monolithic codes and overlapping their computation. I tend to think this
will work better with another approach.

+1 to making the serverless system smarter in managing and running the code
at scale. I don't think the current state is there right now. There are
limitations which could be improved by simply allowing developers to
control which action can be invoked concurrently. We could also consider
designing the system to "learn" this intent by observing how the action is
configured by the developer: if it's an HTTP endpoint, or an event handler.

As long as today we can improve the performance by allowing concurrency in
actions, and by invoking them faster, why would we not benefit from this
now, and update the implementation later, once the system improves ? Or are
there better ways available now to match this performance that are not
captured in the proposal ?


On Sat, Jul 1, 2017 at 10:29 PM Alex Glikson <GLIKSON@il.ibm.com> wrote:

> My main point is - interactive Web applications is certainly not the only
> case which is sensitive to latency (or throughput) under variable load.
> Think of an event that a person presses 'emergency' button in an elevator,
> and we need to respond immediately (it might be even more important than
> occasionally getting a timeout on a web page). So, ideally, the solution
> should address *any* (or as many as possible of) such applications.
>
> Regards,
> Alex
>
>
>
> From:   Tyson Norris <tnorris@adobe.com.INVALID>
> To:     "dev@openwhisk.apache.org" <dev@openwhisk.apache.org>
> Date:   02/07/2017 01:35 AM
> Subject:        Re: Improving support for UI driven use cases
>
>
>
>
> > On Jul 1, 2017, at 2:07 PM, Alex Glikson <GLIKSON@il.ibm.com> wrote:
> >
> >> a burst of users will quickly exhaust the system, which is only fine
> for
> > event handling cases, and not fine at all for UI use cases.
> >
> > Can you explain why is it fine for event handling cases?
> > I would assume that the key criteria would be, for example, around
> > throughput and/or latency (and their tradeoff with capacity), and not
> > necessarily the nature of the application per se.
> >
> > Regards,
> > Alex
>
> Sure - with event handling, where blocking=false, or where a timeout
> response of 202 (and fetch the response later) is tolerable,  exhausting
> container resources will simply mean that the latency goes up based on the
> number of events generated after the point of saturation.  If you can only
> process 100 events at one time, an arrival of 1000 events at the same time
> means that the second 100 events will only be processed after the first
> 100 (twice normal latency), third 100 events after that (3 times normal
> latency), 4th 100 events after that (4 times normal latency) etc. But if
> no user is sitting at a browser waiting for a response, it is unlikely
> they care whether the processing occurs 10ms or 10min after the triggering
> event. (This is exaggerating, but you get the point)
>
> In the case a user is staring at a browser waiting for response, such a
> variance in latency just due to the raw number of users in the system
> directly relating to the raw number of containers in the system, will not
> be usable. Consider concurrency not as a panacea for exhausting container
> pool resources, but rather a way to dampen the graph of user traffic
> increase vs required container pool increase, making it something like
> 1000:1 (1000 concurrent users requires 1 container) instead of it being a
> 1:1 relationship.
>
> Thanks
> Tyson
>
>
>
>
>

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