Hi, It seems we need to introduce cluster context(which will be persisted) for keeping these runtime changes to policies and also the run time data such as required count.
I will work on this. Thanks. On Sat, Oct 18, 2014 at 10:58 AM, Imesh Gunaratne <im...@apache.org> wrote: > Hi, > > @Raj: What I pointed out is a design issue. Each time we introduce a new > feature we should not introduce new persistence logic unless unavoidable, > rather persistence should happen centrally. > > In this scenario when we update the subscription it should go through a > common flow and update the in memory data structure and persist the changes. > > @Lakmal: Yes definitely, will introduce a new feature to update policies. > https://issues.apache.org/jira/browse/STRATOS-896 > > Thanks > > On Wed, Oct 15, 2014 at 4:42 PM, Rajkumar Rajaratnam <rajkum...@wso2.com> > wrote: > >> Hi Imesh, >> >> On Wed, Oct 15, 2014 at 4:26 PM, Imesh Gunaratne <im...@apache.org> >> wrote: >> >>> I do not think we need to specifically handle this, manual scaling also >>> need to take the same path as the standard scaling decision. >>> >> >> Hmm.. In manual scaling what we are doing is increasing the min count >> right? Basically we are modifying the cluster object which is already >> created and added to the topology. Please be kind enough to explain me if I >> got it wrong. How it can take the same path as standard scaling? >> >> Thanks. >> >>> >>> On Wed, Oct 15, 2014 at 10:03 AM, Rajkumar Rajaratnam < >>> rajkum...@wso2.com> wrote: >>> >>>> Or else, we can have an API at CC side to update clusters and let CC to >>>> publish ClusterUpdated event to topology topic. AS can simply listen to >>>> this event and update the cluster context accordingly. Then we don't need >>>> to introduce a new topic for AS to publish events and AS is already >>>> listening to topology topic. IMO, this is a good approach. >>>> >>>> Wdyt? >>>> >>>> >>>> On Wednesday, October 15, 2014, Rajkumar Rajaratnam <rajkum...@wso2.com> >>>> wrote: >>>> >>>>> Hi, >>>>> >>>>> As you know, we are now supporting manual scaling for docker >>>>> containers. Autoscaler has an API to update cluster properties like min >>>>> replicas of a particular cluster. >>>>> >>>>> void updateClusterMonitor(String clusterId, Properties properties) >>>>> throws InvalidArgumentException; >>>>> >>>>> We are not persisting anything about clusters at AS side, when we >>>>> shutdown stratos. When we are restarting, we are reading topology and >>>>> create/populate/update cluster monitors. >>>>> >>>>> Hence this new value for min replicas is not persisted when we >>>>> shutdown the stratos. During manual scaling the min replicas is updated >>>>> only in AS side, hence if we restart the stratos, this effect will be >>>>> lost. >>>>> >>>>> So manual scaling should impact the topology. Here is a proposed >>>>> solution. >>>>> >>>>> AS will provide an API to update cluster monitors, that is you can >>>>> update properties of a cluster like min replicas. Once this API is called >>>>> AS will send a *ClusterAltered* event to CC. Once CC gets this event, >>>>> it will validate the properties, update the topology and send a >>>>> *ClusterUpdated* event. Once AS gets this event, AS will update the >>>>> cluster context with new values for properties like min replicas. Until we >>>>> get cluster updated event, AS will not alter any properties. >>>>> Then everything is consistent and manual scaling effects will be >>>>> persisted. >>>>> >>>>> wdyt? >>>>> >>>>> Thanks. >>>>> >>>>> -- >>>>> Rajkumar Rajaratnam >>>>> Software Engineer | WSO2, Inc. >>>>> Mobile +94777568639 | +94783498120 >>>>> >>>> >>>> >>>> -- >>>> Rajkumar Rajaratnam >>>> Software Engineer | WSO2, Inc. >>>> Mobile +94777568639 | +94783498120 >>>> >>>> >>> >>> >>> -- >>> Imesh Gunaratne >>> >>> Technical Lead, WSO2 >>> Committer & PMC Member, Apache Stratos >>> >> >> >> >> -- >> Rajkumar Rajaratnam >> Software Engineer | WSO2, Inc. >> Mobile +94777568639 | +94783498120 >> > > > > -- > Imesh Gunaratne > > Technical Lead, WSO2 > Committer & PMC Member, Apache Stratos > -- -- Lahiru Sandaruwan Committer and PMC member, Apache Stratos, Senior Software Engineer, WSO2 Inc., http://wso2.com lean.enterprise.middleware email: lahi...@wso2.com blog: http://lahiruwrites.blogspot.com/ linked-in: http://lk.linkedin.com/pub/lahiru-sandaruwan/16/153/146
