Load Balancing Extension

Expansion Description

Select one of multiple service providers to call

Extension ports

org.apache.dubbo.rpc.cluster.LoadBalance

Extended configuration

<dubbo:protocol loadbalance="xxx" />
<!-- Default value setting, when <dubbo:protocol> does not configure loadbalance, use this configuration -->
<dubbo:provider loadbalance="xxx" />

Known extensions

  • org.apache.dubbo.rpc.cluster.loadbalance.RandomLoadBalance
  • org.apache.dubbo.rpc.cluster.loadbalance.RoundRobinLoadBalance
  • org.apache.dubbo.rpc.cluster.loadbalance.LeastActiveLoadBalance
  • org.apache.dubbo.rpc.cluster.loadbalance.ConsistentHashLoadBalance
  • org.apache.dubbo.rpc.cluster.loadbalance.ShortestResponseLoadBalance

Extended example

Maven project structure:

src
 |-main
    |-java
        |-com
            |-xxx
                |-XxxLoadBalance.java (implements the LoadBalance interface)
    |-resources
        |-META-INF
            |-dubbo
                |-org.apache.dubbo.rpc.cluster.LoadBalance (plain text file, content: xxx=com.xxx.XxxLoadBalance)

XxxLoadBalance.java:

package com.xxx;
 
import org.apache.dubbo.rpc.cluster.LoadBalance;
import org.apache.dubbo.rpc.Invoker;
import org.apache.dubbo.rpc.Invocation;
import org.apache.dubbo.rpc.RpcException;
 
public class XxxLoadBalance implements LoadBalance {
    public <T> Invoker<T> select(List<Invoker<T>> invokers, Invocation invocation) throws RpcException {
        //...
    }
}

META-INF/dubbo/org.apache.dubbo.rpc.cluster.LoadBalance:

xxx=com.xxx.XxxLoadBalance

Last modified January 2, 2023: Enhance en docs (#1798) (95a9f4f6c)