Initially I thought the cluster awareness plays a role in throttle decision making within a cluster, but now I see that was a bit of a silly thought :). The ClusterAwareCallerContext can accommodate the additional info needed for cluster replication. +1. We will have one decision engine.
Regards, Manoj On Wed, Jan 29, 2014 at 5:17 PM, Afkham Azeez <[email protected]> wrote: > Again, we don't need 2 engines, and an AbstractEngine. Depending on > whether Hazelcast is available or not, the engine will work accordingly. We > need a single class. Better to keep things simple. > > Azeez > > > On Wed, Jan 29, 2014 at 1:36 PM, Manoj Fernando <[email protected]> wrote: > >> @Sanjeewa - Yes, we will have to consider the policy loading part as well >> (basically to instantiate a CallerConfiguration object based on throttling >> policies). >> >> Throttle replication and Counter updating is indeed a task of the engine. >> We have basically created 2 engine >> implementations... ClusterAwareThrottleDecisionEngine >> and SimpleThrottleDecisionEngine, The former will depend on an >> ExecutorService to plumb with Hazelcast to maintain a cluster wide counter. >> >> Regards, >> Manoj >> >> >> On Tue, Jan 28, 2014 at 11:43 AM, Sanjeewa Malalgoda >> <[email protected]>wrote: >> >>> >>> >>> >>> On Tue, Jan 28, 2014 at 7:31 AM, Manoj Fernando <[email protected]> wrote: >>> >>>> Thought of some improvements. >>>> >>>> - We shall have an AbstractThrottleDecisionEngine so that we can extend >>>> the core to support various decision engines later on (to accommodate >>>> suggestions from Suho and Senaka). >>>> >>> +1 for doing this. Then we might need methods like >>> loadThrottlingPolicy(Policy throttlePolicy) and canAccess(ThrottleContext >>> context). Then we can call underlying throttle engine with necessary data >>> and data format(based on throttle engine implementation - it can be either >>> siddhi based engine or current throttling implementation). AFAIU >>> replication and counter updating should be a task of throttle decision >>> engine. WDYT? >>> >>> Thanks, >>> sanjeewa. >>> >>>> - Make CallerContext abstract so extend into ClusterAwareCallerContext >>>> and SingleNodeCallerContext. >>>> >>>> Regards, >>>> Manoj >>>> >>>> >>>> On Mon, Jan 27, 2014 at 5:33 PM, Manoj Fernando <[email protected]>wrote: >>>> >>>>> Initial code checked in @ http://svn.wso2.org/repos/wso2/people/manojf. >>>>> >>>>> Next : implementing periodic counter replication, persistence. >>>>> >>>>> - Manoj >>>>> >>>>> >>>>> On Mon, Jan 27, 2014 at 9:16 AM, Srinath Perera <[email protected]>wrote: >>>>> >>>>>> Hi Suho, >>>>>> >>>>>> I think we need throttling to work without having to run a >>>>>> distributed CEP. Using Siddhi is fine, as that is transparent, but need >>>>>> for >>>>>> Strom to run thottling usecae is too much IMO. >>>>>> >>>>>> --Srinath >>>>>> >>>>>> >>>>>> On Fri, Jan 3, 2014 at 4:55 PM, Sriskandarajah Suhothayan < >>>>>> [email protected]> wrote: >>>>>> >>>>>>> Is there any possibility of using Distributed CEP/Siddhi here? >>>>>>> Because with Siddhi we can have some flexibility in the way we want to >>>>>>> throttle and throttling is a common usecase of CEP. Its underline >>>>>>> architecture also uses Hazelcast or Storm for distributed processing. >>>>>>> >>>>>>> Regards >>>>>>> Suho >>>>>>> >>>>>>> >>>>>>> On Tue, Dec 24, 2013 at 8:54 AM, Manoj Fernando <[email protected]>wrote: >>>>>>> >>>>>>>> +1. Changing caller contexts in to a Hazlecast map would require >>>>>>>> some significant changes to the throttle core, which may eventually be >>>>>>>> re-written. >>>>>>>> >>>>>>>> Will update the design. >>>>>>>> >>>>>>>> Thanks, >>>>>>>> Manoj >>>>>>>> >>>>>>>> >>>>>>>> On Mon, Dec 23, 2013 at 4:09 PM, Srinath Perera >>>>>>>> <[email protected]>wrote: >>>>>>>> >>>>>>>>> Manoj, above plan look good. >>>>>>>>> >>>>>>>>> I chatted with Azeez, and we cannot register a Entry listener as I >>>>>>>>> mentioned before because hazecast does not support entry listeners for >>>>>>>>> atomic long. >>>>>>>>> >>>>>>>>> --Srinath >>>>>>>>> >>>>>>>>> >>>>>>>>> On Mon, Dec 23, 2013 at 11:15 AM, Manoj Fernando >>>>>>>>> <[email protected]>wrote: >>>>>>>>> >>>>>>>>>> Short update after the discussion with Azeez. >>>>>>>>>> >>>>>>>>>> - The need to re-write the throttle core is still at large, so >>>>>>>>>> the best was to see how we can decouple the persistence logic from >>>>>>>>>> the >>>>>>>>>> throttle core (at least as much as possible). >>>>>>>>>> - A cluster updatable global counter will be included to the >>>>>>>>>> ThrottleContext. The idea is that each node will periodically >>>>>>>>>> broadcast >>>>>>>>>> the local counter info to the members in the cluster and the >>>>>>>>>> ThrottleConfiguration will update the value of the Global counter >>>>>>>>>> summing >>>>>>>>>> up the local counter values. >>>>>>>>>> - The ThrottleConfiguration will also push the global counter >>>>>>>>>> values to the Axis2 Configuration Context; a K, V pairs identified >>>>>>>>>> by the >>>>>>>>>> ThrottleContext ID. >>>>>>>>>> - A new platform component needs to be written to read the >>>>>>>>>> throttle related Axis2 Config Context list and persist them >>>>>>>>>> periodically >>>>>>>>>> (duration configurable). The throttle core will have no visibility >>>>>>>>>> into >>>>>>>>>> this persistence logic, so this will be completely decoupled. >>>>>>>>>> - So who should do the persistence? We can start with letting >>>>>>>>>> all nodes to persist first, but later (or in parallel) we can >>>>>>>>>> improve the >>>>>>>>>> Hazlecast's leader election (if that's not already there), so that >>>>>>>>>> the >>>>>>>>>> leader takes the responsibility of persisting. >>>>>>>>>> - The counters will be read off the persistence store at the time >>>>>>>>>> of Hazlecast Leader election takes place? (An alternative is to load >>>>>>>>>> the >>>>>>>>>> global counters at the init of ThrottleConfiguration but that means >>>>>>>>>> coupling throttle core with persistence.) >>>>>>>>>> >>>>>>>>>> I will update the design accordingly. >>>>>>>>>> >>>>>>>>>> Any more thoughts or suggestions? >>>>>>>>>> >>>>>>>>>> Regards, >>>>>>>>>> Manoj >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Thu, Dec 19, 2013 at 12:30 PM, Manoj Fernando <[email protected] >>>>>>>>>> > wrote: >>>>>>>>>> >>>>>>>>>>> +1. Let me setup a time. >>>>>>>>>>> >>>>>>>>>>> Regards, >>>>>>>>>>> Manoj >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Thursday, December 19, 2013, Srinath Perera wrote: >>>>>>>>>>> >>>>>>>>>>>> We need Azeez's feedback. Shall you, myself, and Azeez chat >>>>>>>>>>>> sometime and decide on the first Arch design? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Thu, Dec 19, 2013 at 11:55 AM, Manoj Fernando < >>>>>>>>>>>> [email protected]> wrote: >>>>>>>>>>>> >>>>>>>>>>>> Hi Srinath, >>>>>>>>>>>> >>>>>>>>>>>> That sounds like a much cleaner solution. We can perhaps use >>>>>>>>>>>> the native map-store declarative [1] which I think does something >>>>>>>>>>>> similar. >>>>>>>>>>>> It may sound a little silly to ask... but are we keeping >>>>>>>>>>>> Hazlecast active >>>>>>>>>>>> on a single node environment as well? :) Otherwise we will have to >>>>>>>>>>>> handle >>>>>>>>>>>> persistence on a single node in a different way. This is with the >>>>>>>>>>>> assumption of needing to persist throttle data on a single node >>>>>>>>>>>> environment >>>>>>>>>>>> as well (but questioning if we really need to do that is not >>>>>>>>>>>> totally >>>>>>>>>>>> invalid IMO). >>>>>>>>>>>> >>>>>>>>>>>> Shall we go ahead with the Hazlecast option targeting cluster >>>>>>>>>>>> deployments then? >>>>>>>>>>>> >>>>>>>>>>>> - Manoj >>>>>>>>>>>> >>>>>>>>>>>> [1] https://code.google.com/p/hazelcast/wiki/MapPersistence >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Thu, Dec 19, 2013 at 10:51 AM, Srinath Perera < >>>>>>>>>>>> [email protected]> wrote: >>>>>>>>>>>> >>>>>>>>>>>> One another way to do this use Hazelcast and then use "though >>>>>>>>>>>> cache" or "Change listener's" in Hazecast for persistence. >>>>>>>>>>>> >>>>>>>>>>>> --Srinath >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Tue, Dec 17, 2013 at 4:49 PM, Manoj Fernando < >>>>>>>>>>>> [email protected]> wrote: >>>>>>>>>>>> >>>>>>>>>>>> +1 for persisting through a single (elected?) node, and let >>>>>>>>>>>> Hazlecast do the replication. >>>>>>>>>>>> >>>>>>>>>>>> I took into consideration the need to persist periodically >>>>>>>>>>>> instead of at each and every request (by spawning a separate >>>>>>>>>>>> thread that >>>>>>>>>>>> has access to the callerContext map)... so yes... we should think >>>>>>>>>>>> in the >>>>>>>>>>>> same way for replicating the counters across the cluster as well. >>>>>>>>>>>> >>>>>>>>>>>> Instead of using a global counter, can we perhaps use the last >>>>>>>>>>>> updated timestamp of each CallerContext? It's actually not a >>>>>>>>>>>> single >>>>>>>>>>>> counter we need to deal with, and each CallerContext instance will >>>>>>>>>>>> have >>>>>>>>>>>> separate counters mapped to their throttling policy AFAIK. >>>>>>>>>>>> Therefore, I >>>>>>>>>>>> think its probably better to update CallerContext instances based >>>>>>>>>>>> on the >>>>>>>>>>>> last update timestamp. >>>>>>>>>>>> >>>>>>>>>>>> WDYT? >>>>>>>>>>>> >>>>>>>>>>>> If agree, then I need to figure out how to make delayed >>>>>>>>>>>> replication on hazlecast (is it through >>>>>>>>>>>> the hazelcast.heartbeat.interval.seconds config item?) >>>>>>>>>>>> >>>>>>>>>>>> Regards, >>>>>>>>>>>> Manoj >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Tue, Dec 17, 2013 at 4:22 PM, Srinath Perera < >>>>>>>>>>>> [email protected]> wrote: >>>>>>>>>>>> >>>>>>>>>>>> We need to think it a cluster setup do we need persistence as >>>>>>>>>>>> well? As we can have replication using Hazelcast? >>>>>>>>>>>> >>>>>>>>>>>> If we need persistence, I think it is a good if a single node >>>>>>>>>>>> persists the current throttling values, and if that node fails, >>>>>>>>>>>> someone >>>>>>>>>>>> else takes it place? >>>>>>>>>>>> >>>>>>>>>>>> Current implementation sync the values across the cluster per >>>>>>>>>>>> each message, which introduce significant overhead. I think we >>>>>>>>>>>> should go to >>>>>>>>>>>> a model where each node collects and update the values once few >>>>>>>>>>>> seconds. >>>>>>>>>>>> >>>>>>>>>>>> idea is >>>>>>>>>>>> 1) there is a global counter, that we use to throttle >>>>>>>>>>>> 2) Each node keep a global counter, and periodically it update >>>>>>>>>>>> the global counter using value in location counter and reset the >>>>>>>>>>>> counter >>>>>>>>>>>> and read the current global counter. >>>>>>>>>>>> 3) Until next update, each node make decisions based on local >>>>>>>>>>>> global counter values it has read already >>>>>>>>>>>> >>>>>>>>>>>> This will mean that the throttling will throttle close to the >>>>>>>>>>>> limit, not exactly at the limit. However, IMHO, that is not a >>>>>>>>>>>> problem for >>>>>>>>>>>> throttling usecase. >>>>>>>>>>>> >>>>>>>>>>>> --Srinath >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Mon, Dec 16, 2013 at 7:20 PM, Manoj Fernando < >>>>>>>>>>>> [email protected]> wrot >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> Manoj Fernando >>>>>>>>>>> Director - Solutions Architecture >>>>>>>>>>> >>>>>>>>>>> Contact: >>>>>>>>>>> LK - +94 112 145345 >>>>>>>>>>> Mob: +94 773 759340 >>>>>>>>>>> www.wso2.com >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> Manoj Fernando >>>>>>>>>> Director - Solutions Architecture >>>>>>>>>> >>>>>>>>>> Contact: >>>>>>>>>> LK - +94 112 145345 >>>>>>>>>> Mob: +94 773 759340 >>>>>>>>>> www.wso2.com >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> -- >>>>>>>>> ============================ >>>>>>>>> Srinath Perera, Ph.D. >>>>>>>>> http://people.apache.org/~hemapani/ >>>>>>>>> http://srinathsview.blogspot.com/ >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Manoj Fernando >>>>>>>> Director - Solutions Architecture >>>>>>>> >>>>>>>> Contact: >>>>>>>> LK - +94 112 145345 >>>>>>>> Mob: +94 773 759340 >>>>>>>> www.wso2.com >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Architecture mailing list >>>>>>>> [email protected] >>>>>>>> https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> >>>>>>> *S. Suhothayan * >>>>>>> Associate Technical Lead, >>>>>>> *WSO2 Inc. *http://wso2.com >>>>>>> * <http://wso2.com/>* >>>>>>> lean . enterprise . middleware >>>>>>> >>>>>>> >>>>>>> *cell: (+94) 779 756 757 <%28%2B94%29%20779%20756%20757> | blog: >>>>>>> http://suhothayan.blogspot.com/ <http://suhothayan.blogspot.com/> >>>>>>> twitter: >>>>>>> http://twitter.com/suhothayan <http://twitter.com/suhothayan> | >>>>>>> linked-in: >>>>>>> http://lk.linkedin.com/in/suhothayan >>>>>>> <http://lk.linkedin.com/in/suhothayan>* >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> ============================ >>>>>> Srinath Perera, Ph.D. >>>>>> >>>>>> Director, Research, WSO2 Inc. >>>>>> Visiting Faculty, University of Moratuwa >>>>>> Member, Apache Software Foundation >>>>>> Research Scientist, Lanka Software Foundation >>>>>> Blog: http://srinathsview.blogspot.com/ >>>>>> Photos: http://www.flickr.com/photos/hemapani/ >>>>>> Phone: 0772360902 >>>>>> >>>>>> _______________________________________________ >>>>>> Architecture mailing list >>>>>> [email protected] >>>>>> https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture >>>>>> >>>>>> >>>>> >>>>> >>>>> -- >>>>> Manoj Fernando >>>>> Director - Solutions Architecture >>>>> >>>>> Contact: >>>>> LK - +94 112 145345 >>>>> Mob: +94 773 759340 >>>>> www.wso2.com >>>>> >>>> >>>> >>>> >>>> -- >>>> Manoj Fernando >>>> Director - Solutions Architecture >>>> >>>> Contact: >>>> LK - +94 112 145345 >>>> Mob: +94 773 759340 >>>> www.wso2.com >>>> >>>> _______________________________________________ >>>> Architecture mailing list >>>> [email protected] >>>> https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture >>>> >>>> >>> >>> >>> -- >>> >>> *Sanjeewa Malalgoda* >>> Senior Software Engineer >>> WSO2 Inc. >>> Mobile : +94713068779 >>> >>> <http://sanjeewamalalgoda.blogspot.com/>blog >>> :http://sanjeewamalalgoda.blogspot.com/<http://sanjeewamalalgoda.blogspot.com/> >>> >>> >>> >>> _______________________________________________ >>> Architecture mailing list >>> [email protected] >>> https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture >>> >>> >> >> >> -- >> Manoj Fernando >> Director - Solutions Architecture >> >> Contact: >> LK - +94 112 145345 >> Mob: +94 773 759340 >> www.wso2.com >> >> _______________________________________________ >> Architecture mailing list >> [email protected] >> https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture >> >> > > > -- > *Afkham Azeez* > Director of Architecture; WSO2, Inc.; http://wso2.com > Member; Apache Software Foundation; http://www.apache.org/ > * <http://www.apache.org/>* > *email: **[email protected]* <[email protected]> > * cell: +94 77 3320919 <%2B94%2077%203320919> blog: * > *http://blog.afkham.org* <http://blog.afkham.org> > *twitter: **http://twitter.com/afkham_azeez*<http://twitter.com/afkham_azeez> > * linked-in: **http://lk.linkedin.com/in/afkhamazeez > <http://lk.linkedin.com/in/afkhamazeez>* > > *Lean . Enterprise . Middleware* > > _______________________________________________ > Architecture mailing list > [email protected] > https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture > > -- Manoj Fernando Director - Solutions Architecture Contact: LK - +94 112 145345 Mob: +94 773 759340 www.wso2.com
_______________________________________________ Architecture mailing list [email protected] https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture
