如何在 cloudwatch 中将 2 个搜索指标与数学表达式结合起来？

Question

我正在尝试获取当运行 lambda 在 cloudwatch 上的图表中显示时使用的内存百分比。我知道还有其他方法可以提取数据，但由于超出此问题范围的原因，我想坚持使用搜索来提取指标。

我有下图

{
    "metrics": [
        [ { "expression": "SEARCH('{SomeMetricNamespace} MetricName=\"MemorySize\"', 'Average', 300)", "id": "m1", "visible": "true" } ],
        [ { "expression": "SEARCH('{SomeMetricNamespace} MetricName=\"MaxMemoryUsed\"', 'Average', 300)", "id": "m2", "visible": "true" } ],
        [ { "expression": "m2/m1*100", "label": "pecentage memory used", "id": "e1", "stat": "Average" } ]
    ],
    "view": "timeSeries",
    "stacked": false,
    "region": "us-west-2",
    "stat": "Average",
    "period": 300,
    "title": "Memory",
    "yAxis": {
        "left": {
            "label": "Percentage Usage",
            "showUnits": false
        }
    },
    "liveData": false
}

我遇到的错误

Error in expression e1 [Unsupported operand type(s) for /: '[Array[TimeSeries], Array[TimeSeries]]']

有没有办法结合前 2 个表达式来给我使用的内存百分比？

Answer 1

表达式的结果是时间序列数组，因此您不能直接应用操作 (+ - * / ^)。作为解决方法，您可以将每个时间序列转换为每个表达式的单个值（平均值），然后计算百分比。

来源应该与此类似：

{
"metrics": [
    [ { "expression": "SEARCH('{SomeMetricNamespace} MetricName=\"MemorySize\"', 'Average', 300)", "id": "m1", "visible": "false" } ],
    [ { "expression": "SEARCH('{SomeMetricNamespace} MetricName=\"MaxMemoryUsed\"', 'Average', 300)", "id": "m2", "visible": "false" } ],
    [ { "expression": "AVG(m1)", "label": "AVGMemorySize", "id": "e1", "visible": "false" } ],
    [ { "expression": "AVG(m2)", "label": "AVGMaxMemoryUsed", "id": "e2", "visible": "false" } ],
    [ { "expression": "e2/e1*100", "label": "pecentage memory used", "id": "e3", "stat": "Average" } ]

    ],
    "view": "timeSeries",
    "stacked": false,
    "region": "us-west-2",
    "stat": "Average",
    "period": 300,
    "title": "Memory",
    "yAxis": {
        "left": {
            "label": "Percentage Usage",
            "showUnits": false
        }
    },
    "liveData": false
}

如何在 cloudwatch 中将 2 个搜索指标与数学表达式结合起来？

How do I combine 2 search metrics with math expression in cloudwatch?

metrics

amazon-web-services

amazon-cloudwatch