PromQL 从⼊⻔到精通 对于 Prometheus 生态的监控系统，PromQL 是必备技能，本文着重点讲解这个查询语言，掺 杂一些生产实践场景，希望对你有所帮助。 ? 本文作者：秦晓辉，Open-Falcon、Nightingale 等开源项目创始人之一，极客时间《运 维监控系统实战笔记》作者；当前在创业（快猫星云联创），为客户提供监控/可观测性产品 方案，有需求的朋友欢迎联系我的微信 不动上报给监控服务端，那计算增量、计算速率这个需求，就要放到服务端来实现了，所以服务 端必须要能对这种类型的数据建模抽象，也就是所谓的 Counter 类型。 时序数据 PromQL 就是查询时序数据的一种 Query Language，要想对 PromQL 有了解，得先搞清楚时 序数据。 认识时序数据 我们先来看一张图，图上是 5 台机器的内存可用率： 每个机器的内存可用率数据，体现为图上的一条线，我们称为 文档中有一个章节专门介绍函数，各个函数的介绍中，都会写明是用于 instant- vector，还是用于 range-vector，如果不理解查询类型，就无法很好的应用这些函数。 查询选择器 PromQL大括号里的部分是 selector，查询选择器，用于从一大堆监控数据中，过滤出真正关心 的数据，在 Prometheus 生态里，时序数据的标识，就是一堆标签集合，所以这里的过滤，就 是针对标签做过滤，支持四类操作符：

points Highly dynamic, built-in service discovery No hierarchical model, n-dimensional label set PromQL: for processing, graphing, alerting, and export Simple operation Highly efficient Richard Hartmann Prometheus Deep Dive Introduction Intro 2.0 to 2.2.1 2.4 - 2.6 Beyond Outro PromQL Quick is not quick enough Brian Brazil optimized PromQL 5x faster for time vector functions 100x reduction in garbage to collect

points Highly dynamic, built-in service discovery No hierarchical model, n-dimensional label set PromQL: for processing, graphing, alerting, and export Simple operation Highly efficient Richard Hartmann @TwitchiH & @fredbrancz Intro to Prometheus Introduction Background Operations & observability Outro PromQL vs SQL avg by(city) (temperature_celsius{country=" germany" }) SELECT city, AVG(value) FROM temperature_celsius

in the new version, rate() and histogram_quantile() functions, producing the same result as their PromQL counterparts, have been added. Other new additions to complement this functionality are the bucket_rate_foreach() differences and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences 354 PromQL instant vector selector Zabbix Supported foreach functions: bucket_rate_foreach Functionally corresponds to ’histogram_quantile’ of PromQL. Returns -1 if values of the last ’Infinity’ bucket (”+inf”) are equal to 0. Examples: => his-

comparison The following table lists differences and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences value (Prometheus pattern) Array of metrics for single value in JSON (Prometheus to JSON) 291 PromQL instant vector selector Zabbix Prometheus preprocessing Label match- ing op- er- a- tors that equals string {=””,...} {=””,...} 292 PromQL instant vector selector Zabbix Prometheus preprocessing Selecting by value

comparison The following table lists differences and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences value (Prometheus pattern) Array of metrics for single value in JSON (Prometheus to JSON) 308 PromQL instant vector selector Zabbix Prometheus preprocessing Label match- ing op- er- a- tors that equals string {=””,...} {=””,...} 309 PromQL instant vector selector Zabbix Prometheus preprocessing Selecting by value

differences and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences 316 PromQL instant vector selector Zabbix bucket_rate_foreach Supported only in calculated items. Functionally corresponds to ’histogram_quantile’ of PromQL. Returns -1 if values of the last ’Infinity’ bucket (”+inf”) are equal to 0. Example: => his- See common parameters. Supported value types: float, int Functionally corresponds to ’rate’ of PromQL. Example: => rate(/host/key,30s) → If the monotonic increase over 30 seconds is 20, this function

and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences 357 PromQL instant vector selector that matches reg- u- lar ex- pres- sion {__name__=~””} {__name__=~””} 358 PromQL instant vector selector Zabbix Prometheus preprocessing Selecting by value

and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences 395 PromQL instant vector selector that matches reg- u- lar ex- pres- sion {__name__=~””} {__name__=~””} 396 PromQL instant vector selector Zabbix Prometheus preprocessing Selecting by value

and similarities between PromQL and Zabbix Prometheus preprocessing query language. PromQL instant vector selector Zabbix Prometheus preprocessing Differences 384 PromQL instant vector selector that matches reg- u- lar ex- pres- sion {__name__=~””} {__name__=~””} 385 PromQL instant vector selector Zabbix Prometheus preprocessing Selecting by value