+1 Good idea Mike
On 1/19/17 08:55, Michael Stolz wrote:
Instead of hopping out to a client, you could get horizontal scale and
asynchronous processing by using an AsyncEventListener in the servers.
That will take care of multi-threading and queuing and all the
plumbing, and you just go ahead and write your processing code and
deploy it as AsyncEventListeners. This gives you guaranteed ordering
semantics for each key as well.
I *think* it even gives you a notion of H/A so that if the primary
fails the queued messages will be processed by a secondary. (I know
the WAN Gateway does and it uses pretty much the same plumbing under
the covers).
--
Mike Stolz
Principal Engineer, GemFire Product Manager
Mobile: 631-835-4771
On Thu, Jan 19, 2017 at 11:21 AM, Udo Kohlmeyer <[email protected]
<mailto:[email protected]>> wrote:
Hi there Paul,
Firstly, your use case looks really interesting and hope to see a
few more posts on how you use Geode further. Keep us informed we
like to hear what you guys are doing with GEODE! :)
The subscription or CQ (continuous query) paradigm is, as stated,
a 1:1 relationship. When a client registers interest on a region
that client will be notified. This is more of a topic semantic
rather than a queue semantic.
Although this is not the first time I've heard the request for
this kind of functionality. To best explain why GEODE, currently,
implements the 1:1 relationship has got to do with guaranteed
delivery and in-order delivery. If we use a queue semantic, with
multiple clients being able to process data in a balanced manner,
we end up with potential out-of-order processing of messages. In
addition to that it now becomes significantly harder to track and
n deal with client failures and the potential replaying of messages.
But that said, I have seen other users resolve this problem and
could detail some approaches in a later correspondence if you'd like.
--Udo
On 1/19/17 03:39, Paul Perez wrote:
Hello All,
As explained in a previous email, we try to use Geode to process
and aggregate a stream of Traces. Our requirement is to process
billions of simple traces every day.
We imagine the aggregation process in many steps.
One: traces are generated by a tiers tools and stored in a first
geode region
Two: once a trace put in the first region we use the async
event feature to invoke a client that executes the first
aggregation steps. Then the result will be put in a second region.
Three: the second aggregation step is in the same way, when
traces are put in the second region, then an asynchronous event
is sent to the client to execute the second part of the
aggregation etc.…
For scalability purposes, we plan to use many clients that could
receive the events and execute the aggregation and put the
results back to Geode.
Consequently, as far as we understand the documentation, when an
entry is put in a region, each client that registered an interest
receives an event and aggregate the trace. So, the trace will be
aggregated many times.
My question is: If many clients are registered, could we
configure the region to send randomly, the event to one client only.
A subsidiary question: Do we have the same behaviour with the
function execution feature or it could be an alternative in that
case
Thank you for your help
Best regards
Paul
