You can still have a near cache embedded into your app using the client/server model of GemFire. Just declare the Region on the client side to be CACHING_PROXY and it will keep a local cache that can be updated from changes on the servers.
-- Mike Stolz Principal Engineer, GemFire Product Manager Mobile: 631-835-4771 On Tue, Nov 15, 2016 at 12:47 AM, Amit Pandey <amit.pandey2...@gmail.com> wrote: > Also for clarification I was planning to do it for a couple of replicated > caches. > > > > On Tue, Nov 15, 2016 at 10:58 AM, Amit Pandey <amit.pandey2...@gmail.com> > wrote: > >> Thanks John and Michael. >> >> I can use client/server no problem. >> >> However my reason to use an embedded Geode was that based on my >> experience with other memory Grids its always faster to have it embedded. >> And I have some requirements for extremely low latency so I thought it >> would have saved some time and given better latency than having the >> client/server model. >> >> On Tue, Nov 15, 2016 at 9:15 AM, John Blum <jb...@pivotal.io> wrote: >> >>> @Mike - correct me if I am wrong, and I wouldn't recommend this, but... >>> >>> You could emulate a pub/sub system even with peers by taking advantage >>> of a Subscription >>> <http://geode.incubator.apache.org/docs/guide/reference/topics/cache_xml.html#subscription-attributes> >>> [1] >>> policy on peer *Regions* (REPLICATE or PARTITION, either or). I.e. a >>> Region's Subscription policy controls what data is replicated between them, >>> which in effect, could serve a similar purpose to topics and what data >>> events a peer Region receives. Then a CacheListener registered on the >>> Region could process events when entries (of interests expressed through >>> the Region Subscription policy) are updated. >>> >>> Of course, this is a superficially limited approach and not advisable >>> for any practical use of a Region's Subscription policy, IMO. First, you >>> would need to pre-populate the Region with keys (for events) you are >>> interested in. Then, you would set the Subscription interest-policy to >>> "cache-content" where your peer would then be notified of updates from any >>> other peer also defining the same Region and, as well, also storing the >>> same key/value. So, as you can see, this is not a intended use of this >>> feature, but it is doable. You can read additional information here >>> <http://geode.incubator.apache.org/docs/guide/developing/events/configure_p2p_event_messaging.html> >>> [2]. >>> >>> As @Mike points out, a better approach it to use the client/server >>> topology >>> <http://geode.incubator.apache.org/docs/guide/topologies_and_comm/cs_configuration/chapter_overview.html> >>> [3] >>> and Register Interests >>> <http://geode.incubator.apache.org/docs/guide/developing/events/configure_client_server_event_messaging.html> >>> [4], >>> or better yet, use CQs >>> <http://geode.incubator.apache.org/docs/guide/developing/continuous_querying/chapter_overview.html> >>> [5]. >>> >>> Hope this helps. >>> >>> Cheers, >>> John >>> >>> >>> [1] http://geode.incubator.apache.org/docs/guide/reference/t >>> opics/cache_xml.html#subscription-attributes >>> [2] http://geode.incubator.apache.org/docs/guide/developing/ >>> events/configure_p2p_event_messaging.html >>> [3] http://geode.incubator.apache.org/docs/guide/topologies_ >>> and_comm/cs_configuration/chapter_overview.html >>> [4] http://geode.incubator.apache.org/docs/guide/developing/ >>> events/configure_client_server_event_messaging.html >>> [5] http://geode.incubator.apache.org/docs/guide/developing/ >>> continuous_querying/chapter_overview.html >>> >>> >>> On Mon, Nov 14, 2016 at 2:57 PM, Michael Stolz <mst...@pivotal.io> >>> wrote: >>> >>>> Ok Got it. >>>> But Peer caches can't do pub/sub unless they go to the extra trouble of >>>> setting up a pool, whereas clients get a pool automatically. >>>> >>>> -- >>>> Mike Stolz >>>> Principal Engineer, GemFire Product Manager >>>> Mobile: 631-835-4771 >>>> >>>> On Mon, Nov 14, 2016 at 3:02 PM, John Blum <jb...@pivotal.io> wrote: >>>> >>>>> Well, what I think Amit means (correct me if I am wrong) is the Geode >>>>> embedded peer cache use case, meaning the application is also a peer cache >>>>> in the cluster, while not the most common UC (nor maybe recommended in >>>>> most >>>>> UCs), it is a valid UC none-the-less. >>>>> >>>>> It is to have your application participate a peer in the Geode cluster >>>>> by simply constructing a peer Cache using the CacheFactory >>>>> <http://geode.incubator.apache.org/releases/latest/javadoc/org/apache/geode/cache/CacheFactory.html> >>>>> [1], >>>>> and setting the locators property have your application join existing >>>>> cluster, something like so... >>>>> >>>>> Cache peerCache = new CacheFactory().set("locators", >>>>> "<host>[<port>]").set(..)...create(); >>>>> >>>>> You can also do this in SDG with... >>>>> >>>>> <util:properties id="geodeProperties"> >>>>> <prop key="name">MyApplication</prop> >>>>> <prop key="mcast-port">0</prop> >>>>> <prop key="log-level">${geode.log.level:config}</prop> >>>>> <prop key="locators">${geode.locators.host-port:localhost[10334]}</ >>>>> prop> >>>>> <prop key="start-locator">${geode.locator.embedded.host-port:}</prop> >>>>> </util:properties> >>>>> >>>>> <gfe:cache properties-ref="geodeProperties"/> >>>>> >>>>> The <gfe:cache> element created a "peer" cache (as opposed to the >>>>> <gfe:client-cache> element). >>>>> >>>>> You are then free to create Regions used by your application as >>>>> necessary. >>>>> >>>>> I have examples of both GemFire peer and client/server configurations >>>>> here <https://github.com/jxblum/pivotal-gemfire-clientserver-examples> [2] >>>>> and here >>>>> <https://github.com/jxblum/contacts-application/tree/apache-geode> >>>>> [3] (see configuration examples). >>>>> >>>>> Hope this helps. >>>>> >>>>> Cheers, >>>>> John >>>>> >>>>> [1] http://geode.incubator.apache.org/releases/latest/javado >>>>> c/org/apache/geode/cache/CacheFactory.html >>>>> [2] https://github.com/jxblum/pivotal-gemfire-clientserver-examples >>>>> [3] https://github.com/jxblum/contacts-application/tree/apache-geode >>>>> >>>>> >>>>> On Mon, Nov 14, 2016 at 11:28 AM, Michael Stolz <mst...@pivotal.io> >>>>> wrote: >>>>> >>>>>> Geode clients have the ability to registerInterest(key) which works a >>>>>> lot like a topic. >>>>>> >>>>>> Not sure what you mean by using Geode embedded and with a cluster of >>>>>> external processes, but what I THINK you're asking is, can you use the >>>>>> Geode client/server model where the client is embedded into your >>>>>> application process and the servers that are responsible for holding all >>>>>> the data are in a separate cluster. The answer is YES, that is the most >>>>>> common configuration for Geode usage. >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Mike Stolz >>>>>> Principal Engineer, GemFire Product Manager >>>>>> Mobile: 631-835-4771 >>>>>> >>>>>> On Sat, Nov 12, 2016 at 12:41 PM, Amit Pandey < >>>>>> amit.pandey2...@gmail.com> wrote: >>>>>> >>>>>>> Hi Guys, >>>>>>> >>>>>>> Is there any example of public subscribe with geode? Hazelcast and >>>>>>> Ignite seem to have topics, is there any such thing in Geode. >>>>>>> >>>>>>> Also I want to use Geode embedded. Can I use it with a cluster of >>>>>>> external processes as well. >>>>>>> >>>>>>> Regards >>>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> -- >>>>> -John >>>>> 503-504-8657 >>>>> john.blum10101 (skype) >>>>> >>>> >>>> >>> >>> >>> -- >>> -John >>> 503-504-8657 >>> john.blum10101 (skype) >>> >> >> >
