JMeter中的并发

Question

我有一个关于JMeter中并发性和恒定吞吐量的查询。你能帮我做这个吗？

假设我有一个简单的JMeter脚本来测试RESTAPI（get），不同的JMeter参数设置如下。

Number of threads(users)= 5,
Duration = 600 sec(10 minutes), 
Ramp up             = 1 sec

恒定吞吐量定时器

Target throughput=5 per minute,
Calculate throughput based on=all active threads in the current thread group.

假设：Api立即响应，没有任何延迟。

问题

我对JMeter的理解如下：如果我执行脚本，那么JMeter将并发触发5个get请求（因为线程数设置为5），然后JMeter将等待一分钟（因为吞吐量设置为5个/分钟和JMeter已经并发触发了5个请求），然后再次并发触发5个请求，这将持续600秒。我的理解正确吗？

提前谢谢

===========================================JMX文件启动================================

<?xml version="1.0" encoding="UTF-8"?>
<jmeterTestPlan version="1.2" properties="2.9" jmeter="3.0 r1743807">
  <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" 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>
          <intProp name="LoopController.loops">-1</intProp>
        </elementProp>
        <stringProp name="ThreadGroup.num_threads">5</stringProp>
        <stringProp name="ThreadGroup.ramp_time">1</stringProp>
        <longProp name="ThreadGroup.start_time">1472550371000</longProp>
        <longProp name="ThreadGroup.end_time">1472550371000</longProp>
        <boolProp name="ThreadGroup.scheduler">true</boolProp>
        <stringProp name="ThreadGroup.duration">600</stringProp>
        <stringProp name="ThreadGroup.delay"></stringProp>
      </ThreadGroup>
      <hashTree>
        <HTTPSamplerProxy guiclass="HttpTestSampleGui" testclass="HTTPSamplerProxy" testname="Sampler" enabled="true">
          <boolProp name="HTTPSampler.postBodyRaw">true</boolProp>
          <elementProp name="HTTPsampler.Arguments" elementType="Arguments">
            <collectionProp name="Arguments.arguments">
              <elementProp name="" elementType="HTTPArgument">
                <boolProp name="HTTPArgument.always_encode">false</boolProp>
                <stringProp name="Argument.value"></stringProp>
                <stringProp name="Argument.metadata">=</stringProp>
              </elementProp>
            </collectionProp>
          </elementProp>
          <stringProp name="HTTPSampler.domain">reqres.in</stringProp>
          <stringProp name="HTTPSampler.port"></stringProp>
          <stringProp name="HTTPSampler.connect_timeout"></stringProp>
          <stringProp name="HTTPSampler.response_timeout"></stringProp>
          <stringProp name="HTTPSampler.protocol">https</stringProp>
          <stringProp name="HTTPSampler.contentEncoding"></stringProp>
          <stringProp name="HTTPSampler.path">/api/users/2</stringProp>
          <stringProp name="HTTPSampler.method">GET</stringProp>
          <boolProp name="HTTPSampler.follow_redirects">true</boolProp>
          <boolProp name="HTTPSampler.auto_redirects">false</boolProp>
          <boolProp name="HTTPSampler.use_keepalive">true</boolProp>
          <boolProp name="HTTPSampler.DO_MULTIPART_POST">false</boolProp>
          <boolProp name="HTTPSampler.monitor">false</boolProp>
          <stringProp name="HTTPSampler.embedded_url_re"></stringProp>
        </HTTPSamplerProxy>
        <hashTree>
          <ConstantThroughputTimer guiclass="TestBeanGUI" testclass="ConstantThroughputTimer" testname="Constant Throughput Timer" enabled="true">
            <intProp name="calcMode">2</intProp>
            <doubleProp>
              <name>throughput</name>
              <value>5.0</value>
              <savedValue>0.0</savedValue>
            </doubleProp>
          </ConstantThroughputTimer>
          <hashTree/>
        </hashTree>
      </hashTree>
      <ResultCollector guiclass="ViewResultsFullVisualizer" testclass="ResultCollector" testname="Listner" 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>true</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>
</jmeterTestPlan>

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Answer 1

不，JMeter将立即启动5个线程，然后它将保持每分钟5个请求，这意味着每12秒它将击中服务器，它将持续10分钟。因此，您总共将有大约50 5个采样器，实际数量将根据您的响应时间而有所不同。

有关更多详细信息，请参阅如何使用JMeter的恒定吞吐量计时器文章。

如果希望JMeter每分钟运行5个并发采样器，则需要进行不同的设置，即：

• 你的取样器
  • 同步计时器-模拟用户的分组数量设置为5