Load Testing CassandraDB with JMeter

Question

I am using the Cassandra JMeter Plugin https://github.com/slowenthal/jmeter-cassandra#cassandra-jmeter-plugin-for-cassandra which i have integrated in apache-JMeter2.9

I have a Cassandra Cluster containing 2 Datacenter and 2 nodes on each datacenter.

JMeter:

Cassandra Connection:

contact points : 192.168.1.50,192.168.1.51,192.168.1.52
keyspace : test_db

Cassandra Sampler

CQL Query : select  * from test_db.feed_yogesh limit 1000;
Consistency Level : QUORUM

Testing Scenario

1.Fetch 1000 records for 1 user

User/Thread : 1
Ramp-Up-Period : 0
Generate Summary Results =      1 in   2.2s =    0.5/s Avg:  2180 Min:  2180 Max:  2180 Err:     0 (0.00%)

2.Fetch 1000 records for 1000 user

I want to test for Multiple Users Concurrently hence I added Ramp-Up-period as 0 which as per JMeter will immediately start all the users.

User/Thread : 1000
RampUp Period : 0
Summary Results =   1000 in    18s =   56.1/s Avg:  6857 Min:  5000 Max: 17044 Err:   987 (98.70%)

It Does start all my user but only 4-5 users return success rest all give me error such as

All host(s) tried for query failed (tried: /192.168.1.50:9042 (com.datastax.driver.core.BusyConnectionException))

But when i Test the same 1000 User giving a Ramp-up-period of 300 it returns all success.

User/Thread : 1000
RampUp Period : 300
Generate Summary Results =   1000 in   301s =    3.3/s Avg:   519 Min:   255 Max:  1811 Err:     0 (0.00%)

Cassndra Sampler.jmx

<?xml version="1.0" encoding="UTF-8"?>
<jmeterTestPlan version="1.2" properties="2.4" jmeter="2.9 r1437961">
  <hashTree>
    <TestPlan guiclass="TestPlanGui" testclass="TestPlan" testname="Test Plan" enabled="true">
      <stringProp name="TestPlan.comments"></stringProp>
      <boolProp name="TestPlan.functional_mode">false</boolProp>
      <boolProp name="TestPlan.serialize_threadgroups">false</boolProp>
      <elementProp name="TestPlan.user_defined_variables" elementType="Arguments" guiclass="ArgumentsPanel" testclass="Arguments" testname="User Defined Variables" enabled="true">
        <collectionProp name="Arguments.arguments"/>
      </elementProp>
      <stringProp name="TestPlan.user_define_classpath"></stringProp>
    </TestPlan>
    <hashTree>
      <ThreadGroup guiclass="ThreadGroupGui" testclass="ThreadGroup" testname="Thread Group" enabled="true">
        <stringProp name="ThreadGroup.on_sample_error">continue</stringProp>
        <elementProp name="ThreadGroup.main_controller" elementType="LoopController" guiclass="LoopControlPanel" testclass="LoopController" testname="Loop Controller" enabled="true">
          <boolProp name="LoopController.continue_forever">false</boolProp>
          <stringProp name="LoopController.loops">1</stringProp>
        </elementProp>
        <stringProp name="ThreadGroup.num_threads">1000</stringProp>
        <stringProp name="ThreadGroup.ramp_time">0</stringProp>
        <longProp name="ThreadGroup.start_time">1420788860000</longProp>
        <longProp name="ThreadGroup.end_time">1420788860000</longProp>
        <boolProp name="ThreadGroup.scheduler">false</boolProp>
        <stringProp name="ThreadGroup.duration"></stringProp>
        <stringProp name="ThreadGroup.delay"></stringProp>
      </ThreadGroup>
      <hashTree>
        <org.apache.cassandra.jmeter.config.CassandraConnection guiclass="TestBeanGUI" testclass="org.apache.cassandra.jmeter.config.CassandraConnection" testname="Cassandra Connection" enabled="true">
          <stringProp name="contactPoints">192.168.1.50,192.168.1.51,192.168.1.52</stringProp>
          <stringProp name="keyspace">test_db</stringProp>
          <stringProp name="loadBalancer">Default</stringProp>
          <stringProp name="localDataCenter"></stringProp>
          <stringProp name="password"></stringProp>
          <stringProp name="sessionName">mydatabase</stringProp>
          <stringProp name="username"></stringProp>
        </org.apache.cassandra.jmeter.config.CassandraConnection>
        <hashTree/>
        <org.apache.cassandra.jmeter.sampler.CassandraSampler guiclass="TestBeanGUI" testclass="org.apache.cassandra.jmeter.sampler.CassandraSampler" testname="Cassandra Sampler" enabled="true">
          <stringProp name="batchSize"></stringProp>
          <stringProp name="consistencyLevel">QUORUM</stringProp>
          <stringProp name="query">select  * from test_db.feed_yogesh limit 1000;</stringProp>
          <stringProp name="queryArguments">Running</stringProp>
          <stringProp name="queryType">Simple Statement</stringProp>
          <stringProp name="resultVariable"></stringProp>
          <stringProp name="sessionName">mydatabase</stringProp>
          <stringProp name="variableNames">VARCHAR</stringProp>
        </org.apache.cassandra.jmeter.sampler.CassandraSampler>
        <hashTree/>
        <ResultCollector guiclass="ViewResultsFullVisualizer" testclass="ResultCollector" testname="View Results Tree" enabled="true">
          <boolProp name="ResultCollector.error_logging">false</boolProp>
          <objProp>
            <name>saveConfig</name>
            <value class="SampleSaveConfiguration">
              <time>true</time>
              <latency>true</latency>
              <timestamp>true</timestamp>
              <success>true</success>
              <label>true</label>
              <code>true</code>
              <message>true</message>
              <threadName>true</threadName>
              <dataType>true</dataType>
              <encoding>false</encoding>
              <assertions>true</assertions>
              <subresults>true</subresults>
              <responseData>false</responseData>
              <samplerData>false</samplerData>
              <xml>false</xml>
              <fieldNames>false</fieldNames>
              <responseHeaders>false</responseHeaders>
              <requestHeaders>false</requestHeaders>
              <responseDataOnError>false</responseDataOnError>
              <saveAssertionResultsFailureMessage>false</saveAssertionResultsFailureMessage>
              <assertionsResultsToSave>0</assertionsResultsToSave>
              <bytes>true</bytes>
            </value>
          </objProp>
          <stringProp name="filename"></stringProp>
        </ResultCollector>
        <hashTree/>
        <ResultCollector guiclass="SummaryReport" testclass="ResultCollector" testname="Summary Report" enabled="true">
          <boolProp name="ResultCollector.error_logging">false</boolProp>
          <objProp>
            <name>saveConfig</name>
            <value class="SampleSaveConfiguration">
              <time>true</time>
              <latency>true</latency>
              <timestamp>true</timestamp>
              <success>true</success>
              <label>true</label>
              <code>true</code>
              <message>true</message>
              <threadName>true</threadName>
              <dataType>true</dataType>
              <encoding>false</encoding>
              <assertions>true</assertions>
              <subresults>true</subresults>
              <responseData>false</responseData>
              <samplerData>false</samplerData>
              <xml>false</xml>
              <fieldNames>false</fieldNames>
              <responseHeaders>false</responseHeaders>
              <requestHeaders>false</requestHeaders>
              <responseDataOnError>false</responseDataOnError>
              <saveAssertionResultsFailureMessage>false</saveAssertionResultsFailureMessage>
              <assertionsResultsToSave>0</assertionsResultsToSave>
              <bytes>true</bytes>
            </value>
          </objProp>
          <stringProp name="filename"></stringProp>
        </ResultCollector>
        <hashTree/>
      </hashTree>
    </hashTree>
  </hashTree>
</jmeterTestPlan>

I am confused, does it mean that multiple user's cannnot read data concurrently do we compulsorily need to add the Ramp-Up-Period value.

Nachiket Kate Nachiket Kate · Accepted Answer · 2015-01-09T12:57:29

Rampup period decides time frame in which users should come online or start hitting load on target.

Your results shows that when you started with 0 rampup that all 1000 users started at the same time (1000 concurrent users hitting DB at the same time). Results show that only few users 1% got passed and rest failed which is expected if proper tuning is not done or DB server does not have enough configuration.

Reason for above behavior could be that your database server is couldn't take that much load at a time. it tried to serve as much as it can but beyond some limit it stopped working.

But when you added ramp up then queries/users hitting db rate was within DB serving limits and thus it served.

What you can check is find out bottleneck or cause of those failures. some reasons could be,

Low connection pool
Lower transaction timeouts
Low configuration
Lack of tuning parameters on DB

There can be many reasons but try with debugging and resolving performance issues and retest again with lower rampup (0 sec is not advised for 1000 users atleast keep 5-10 seconds). If you want 1000 users to hit simulataneously at a point there is called synchronization timer component which can help you.

Load Testing CassandraDB with JMeter

1 Answers