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Josh Elser updated PHOENIX-3654: -------------------------------- Summary: Client-side PQS discovery for thin client (was: Load Balancer for thin client) > Client-side PQS discovery for thin client > ----------------------------------------- > > Key: PHOENIX-3654 > URL: https://issues.apache.org/jira/browse/PHOENIX-3654 > Project: Phoenix > Issue Type: New Feature > Affects Versions: 4.8.0 > Environment: Linux 3.13.0-107-generic kernel, v4.9.0-HBase-0.98 > Reporter: Rahul Shrivastava > Assignee: Rahul Shrivastava > Priority: Major > Fix For: 4.12.0 > > Attachments: LoadBalancerDesign.pdf, Loadbalancer.patch > > Original Estimate: 240h > Remaining Estimate: 240h > > We have been having internal discussion on load balancer for thin client for > PQS. The general consensus we have is to have an embedded load balancer with > the thin client instead of using external load balancer such as haproxy. The > idea is to not to have another layer between client and PQS. This reduces > operational cost for system, which currently leads to delay in executing > projects. > But this also comes with challenge of having an embedded load balancer which > can maintain sticky sessions, do fair load balancing knowing the load > downstream of PQS server. In addition, load balancer needs to know location > of multiple PQS server. Now, the thin client needs to keep track of PQS > servers via zookeeper ( or other means). > In the new design, the client ( PQS client) , it is proposed to have an > embedded load balancer. > Where will the load Balancer sit ? > The load load balancer will embedded within the app server client. > How will the load balancer work ? > Load balancer will contact zookeeper to get location of PQS. In this case, > PQS needs to register to ZK itself once it comes online. Zookeeper location > is in hbase-site.xml. It will maintain a small cache of connection to the > PQS. When a request comes in, it will check for an open connection from the > cache. > How will load balancer know load on PQS ? > To start with, it will pick a random open connection to PQS. This means that > load balancer does not know PQS load. Later , we can augment the code so that > thin client can receive load info from PQS and make intelligent decisions. > How will load balancer maintain sticky sessions ? > While we still need to investigate how to implement sticky sessions. We can > look for some open source implementation for the same. > How will PQS register itself to service locator ? > PQS will have location of zookeeper in hbase-site.xml and it would register > itself to the zookeeper. Thin client will find out PQS location using > zookeeper. -- This message was sent by Atlassian Jira (v8.20.1#820001)