使用 Merge 组合系列

如果要在一个图形上绘制两个系列图形，可以使用“ 合并” 功能。这也可以与 Series 函数结合使用来操作 Y 轴（就像强制它从零开始一样）。

template graph.template {
    subject = ...

    body = `{{template "header" .}}

    <strong>Graph With Merge+Series so Y Axis Starts At Zero</strong>
    <div>{{.Graph .Alert.Vars.graph_merged .Alert.Vars.graph_unit}}</div>
    `
}

alert os.low.memory {
    template = graph.template
    ...
    $graph_time = "1d"
    $graph_host = q("avg:300s-avg:os.mem.percent_free{host=myhost}", $graph_time, "")
    $graph_unit = Notice the Y axis always starts at zero now
    $graph_series = series("value=zero", epoch()-d($graph_time), 0, epoch(),0)
    $graph_merged = merge($graph_host,$graph_series)    
    ...
}