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Percona's CEO Peter Zaitsev talks about using VictoriaMetrics to solve a problem we have with Prometheus rate() function handling.

Use rate for alerts and slow-moving counters, as brief changes in the rate can reset the FOR clause and graphs consisting entirely of rare spikes are hard to read. Note that when combining irate() with an aggregation operator (e.g. sum() ) or a function aggregating over time (any function ending in _over_time ), always take a irate() first, then aggregate.

rate(v range-vector) calculates the per-second average rate of increase of the time series in the range vector. Breaks in monotonicity (such as ...

The "increase" function calculates how much some counter has grown and the "rate" function calculates the amount per second the measure ...

Counters are a Prometheus metric type whose value only goes up, ... you typically want to wrap it in a function like rate() , irate() , or ...

In this case Prometheus takes the difference between the last and first points in each interval (your actual counter increase), divides it by the time difference between the 2 points (on average 45 seconds), then extrapolates that to 1 minute (essentially overestimating it by a factor of 1.(3) -- I'm eyeballing an increase of ~200k over ~50 minutes, so an average rate of about 67 QPS, whereas rate() returns something closer to 90 QPS). This is what happens in the second half of your graph.

Prometheus is an open-source tool for collecting metrics and sending alerts. It was developed by SoundCloud. It has the following primary components: The core Prometheus app – This is responsible for scraping and storing metrics in an internal time series database, or sending data to a remote storage backend.

Now rate over 5m will be: (780-0)/5/60 = 2.6/sec. And irate over 5m will be (only last two data points are used which happen to be only 1m apart) (780-720)/1/60 = 1/sec. Increasing the resolution does not affect the irate function because the last two observed values do not change when you look further back. 5.

Making peace with Prometheus rate() ... and with 15s scrape interval that's exactly the recommended look-back window for rate() function.

The rate() function is a way to measure the increment or decrement of a counter(typically) during a time of period.

19.07.2021 · irate () vs rate () – What’re they telling you? Prometheus makes available great functions for data aggregation by timeline. Among these functions, I focused my analysis on irate () and rate () which give us similar outcomes but they work in different way. Let’s see, by making an example, what happens under the hood to understand how it works.

Apr 13, 2021 · ceil = Rounds UP to the nearest integer. floor = Rounds DOWN to the nearest integer. See more details about the "round" function in the Prometheus documentation here. In your case, you're using "rate" so you get the number of restarts per second * 60 * 5. Which is the same as the number of restarts every 5 minutes.

24.06.2020 · prometheus 常用 函数 详解 1万+ rate函数 （速率 函数 ） rate () 函数 是专门搭配counter数据类型 使用函数 ，功能是取counter在这个时间段中平均每秒的增量 1 获取网卡1m每秒流量平均（此时是有多少网卡将会显示多少网卡的流量） 表达式 rate (node_n et work_ re ceive_bytes_t... Prometheus 监控： rate 与 irate 的区别 热门推荐 palet的专栏 5万+ 对官网文档 …

01.02.2021 · rate () is function to specify the time window for the quantile calculation. Show activity on this post. rate () calculates the amount of events per second (from a counter, that is incemented for every single event) avg () is an aggregation operator to calculate one timeline out of …

17.10.2015 · The rate function takes a time series over a time range, and based on the first and last data points within that range (allowing for counter resets) calculates a per-second rate. As it's based on the whole range, it's effectively an average rate over that range - 5 minutes in this case.

Grafana/Prometheus: Understand Rate Function. Percentage of time with more than 10 errors per second for the last hour: VictoriaMetrics supports Prometheus ...

01.06.2021 · What Is Prometheus Rate? Prometheus rate function is the process of calculating the average per second rate of value increases. You would use this when you want to view how your server CPU usage has increased over a time range or how many requests come in over a time range and how that number increases.

28.02.2020 · First – the problem. rate () functions give you the rate of change of the time series for the Interval supplied, so rate (mysql_global_status_questions [10s]) will basically give us the average number of MySQL questions over the last 10seconds. Everything is great so far.

As the name suggests, it lets you calculate the per-second average rate of how a value is increasing over a period of time. It is the function ...

Feb 02, 2019 · If you query rate (counter [5s]) OTOH, Prometheus will pick all the samples in the range [now () - 5s, now] (5 samples, covering approximately 4 seconds on average, say [t1, v1], [t2, v2], [t3, v3], [t4, v4], [t5, v5]) and (assuming your counter doesn't reset within the interval) will return (v5 - v1) / (t5 - t1).

May 08, 2020 · Both Prometheus and its querying language PromQL have quite a few functions for performing various calculations on the data they have. One of the most widely used functions is rate (), however it is also one of the most misunderstood.