Sample 59: Weighted Round-Robin loadbalancing between 3 endpoints
<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://ws.apache.org/ns/synapse">
<sequence name="main" onError="errorHandler">
<in>
<send>
<endpoint>
<loadbalance
algorithm="org.apache.synapse.endpoints.algorithms.WeightedRoundRobin">
<endpoint>
<address uri="http://localhost:9001/services/LBService1">
<enableAddressing/>
<suspendOnFailure>
<initialDuration>20000</initialDuration>
<progressionFactor>1.0</progressionFactor>
</suspendOnFailure>
</address>
<property name="loadbalance.weight" value="1"/>
</endpoint>
<endpoint>
<address uri="http://localhost:9002/services/LBService1">
<enableAddressing/>
<suspendOnFailure>
<initialDuration>20000</initialDuration>
<progressionFactor>1.0</progressionFactor>
</suspendOnFailure>
</address>
<property name="loadbalance.weight" value="2"/>
</endpoint>
<endpoint>
<address uri="http://localhost:9003/services/LBService1">
<enableAddressing/>
<suspendOnFailure>
<initialDuration>20000</initialDuration>
<progressionFactor>1.0</progressionFactor>
</suspendOnFailure>
</address>
<property name="loadbalance.weight" value="3"/>
</endpoint>
</loadbalance>
</endpoint>
</send>
<drop/>
</in>
<out>
<send/>
</out>
</sequence>
<sequence name="errorHandler">
<makefault response="true">
<code xmlns:tns="http://www.w3.org/2003/05/soap-envelope" value="tns:Receiver"/>
<reason value="COULDN'T SEND THE MESSAGE TO THE SERVER."/>
</makefault>
<send/>
</sequence>
</definitions>
Objective
Objective: Demonstrate the weighted load balancing among a set of
endpoints
Pre-requisites
- Start ESB with sample configuration 59. (i.e. wso2esb-samples -sn 59)
- Deploy the LoadbalanceFailoverService and start three instances of sample Axis2 server as mentioned in sample 52.
- Above configuration sends messages with the weighted loadbalance behaviour. Weight of each leaf
address endpoint is defined by integer value of "loadbalance.weight" property associated with each endpoint.
If weight of a endpoint is x, x number of requests will send to that endpoint before switch to next active endpoint.
To test this, run the loadbalancefailover client to send 100 requests as follows:
Executing the Client
Invoke the sample client as follows
ant loadbalancefailover -Di=100
This client sends 100 requests to the LoadbalanceFailoverService through
ESB. ESB will distribute the load among the three endpoints mentioned in the
configuration in weighted round-robin manner. LoadbalanceFailoverService appends the
name of the server to the response, so that client can determine which server
has processed the message. If you examine the console output of the client,
you can see that requests are processed by three servers as follows:
[java] Request: 1 ==> Response from server: MyServer1
[java] Request: 2 ==> Response from server: MyServer2
[java] Request: 3 ==> Response from server: MyServer2
[java] Request: 4 ==> Response from server: MyServer3
[java] Request: 5 ==> Response from server: MyServer3
[java] Request: 6 ==> Response from server: MyServer3
[java] Request: 7 ==> Response from server: MyServer1
[java] Request: 8 ==> Response from server: MyServer2
[java] Request: 9 ==> Response from server: MyServer2
[java] Request: 10 ==> Response from server: MyServer3
[java] Request: 11 ==> Response from server: MyServer3
[java] Request: 12 ==> Response from server: MyServer3
...
As logs, endpoint with weight 1 received a 1 request and endpoint with weight 2 received 2
requests and etc... in a cycle
Back to Catalog
