What are the types of Metrics known as Statistical Collector?

About

This page is about metrics as telemetry data context (realtime performance, monitoring of system)

A telemetry metric is a time serie with:

• timestamped
• numerical value
• and optional labels

Other name

Monitoring Metrics are also known as:

• Statistical Collector
• Perfcounter (generally on Windows)
• Performance metrics
• Performance data

They are known as statistical data collectors because they gather data and compute statistics. They are used to collect, evaluate and report results, e.g.

• mean residence times of customers
• or the average utilisation of a server.

Aggregated metrics / Statistics

An aggregated metrics is

• calculated from time serie data.
• a statistic(s) (See also the page Counter - Statistics (for Engineers on operational data))

They are event metrics.

Type

Counter

A Counter is a metric that:

• can go only up.
• is reset when the application restarts.
• is used to record occurrences of events like the number of customer arrivals
• is plotted with a rate function over an interval

Car example: the mileage counter.

Gauge

A Gauge is a metric that can go up and down (gauge values are not rates).

Car Example: Speedometers

Timer

A Timer measures both the count of timed events and the total time of all events timed.

Others

• Distribution
• Histogram - A histogram ranks the measured values into predefined classes.
• Regressions: A Regression perform a regressional analysis of two different collected value series (x and y). It reports the number of observations, mean (for x and y), regression and correlation coefficients, standard deviations and interception.

Time series:

• Tallies. A tally records the mean and standard deviation of a (time) series of values. Example: Computing the average time customers spent on a system
• Accumulates: An Accumulate records the mean and standard deviation of a time series of values against different time intervals. Example: System load

See also: Prometheus Metrics Type

Implementation

• Statistical Data Collectors (desmoj.core.statistic package)