如何在Jmeter中更改PerfMon图形图例

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        <stringProp name="ThreadGroup.on_sample_error">continue</stringProp>
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          <boolProp name="LoopController.continue_forever">false</boolProp>
          <stringProp name="LoopController.loops">1</stringProp>
        </elementProp>
        <stringProp name="ThreadGroup.num_threads">1</stringProp>
        <stringProp name="ThreadGroup.ramp_time">1</stringProp>
        <boolProp name="ThreadGroup.scheduler">false</boolProp>
        <stringProp name="ThreadGroup.duration"></stringProp>
        <stringProp name="ThreadGroup.delay"></stringProp>
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              <elementProp name="graphiteHost" elementType="Argument">
                <stringProp name="Argument.name">graphiteHost</stringProp>
                <stringProp name="Argument.value">localhost</stringProp>
                <stringProp name="Argument.metadata">=</stringProp>
              </elementProp>
              <elementProp name="graphitePort" elementType="Argument">
                <stringProp name="Argument.name">graphitePort</stringProp>
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                <stringProp name="Argument.metadata">=</stringProp>
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          </elementProp>
          <stringProp name="classname">org.apache.jmeter.visualizers.backend.graphite.GraphiteBackendListenerClient</stringProp>
        </BackendListener>
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