---
name: "latency-histogram"
section: "1"
platform: "linux"
package: "linuxcnc-uspace"
version: "1:2.9.4-2+deb13u1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/latency-histogram"
---

# latency-histogram(1)

plot a histogram of machine latency

## NAME

latency-histogram - plot a histogram of machine latency

## SYNOPSIS

**latency-histogram** \[**-?\|--help**\] \[**--base** ***ns***\] \[**--servo** ***ns***\] \[**--bbinsize** ***ns***\] \[**--sbinsize** ***ns***\] \[**--bbins** ***ns***\] \[**--sbins** ***ns***\] \[**--logscale** ***0\|1***\] \[**--text** ***note***\] \[**--show**\] \[**--nobase**\] \[**--verbose**\] \[**--nox**\]

## DESCRIPTION

The latency test is important when configuring a LinuxCNC system. An adjunct to the standard latency-test latency-histogram plots the distribution of latency. This can be useful to get a feel for how frequent the high latency excursions are.

LinuxCNC and HAL should not be running, stop with *halrun -U*. Large number of bins and/or small binsizes will slow updates. For single thread, specify **--nobase** (and options for servo thread). Measured latencies outside of the +/- bin range are reported with special end bars. Use **--show** to show count for the off-chart \[pos\|neg\] pin.

More details: https://linuxcnc.org/docs/html/install/latency-test.html

## OPTIONS

- **-?**, **--help**

  Show options and exit.

- **--base** *ns*

  base thread interval, default: 25000, min: 5000

- **--servo** *ns*

  servo thread interval, default: 1000000, min: 25000

- **--bbinsize** *ns*

  base bin size, default: 100

- **--sbinsize** *ns*

  servo bin size, default: 100

- **--bbins** *ns*

  base bins, default: 200

- **--sbins** *ns*

  servo bins, default: 200

- **--logscale** *0\|1*

  y axis log scale, default: 1

- **--text** *note*

  additional note, default: ""

- **--show**

  show count of undisplayed bins

- **--nobase**

  servo thread only

- **--verbose**

  progress and debug

- **--nox**

  no GUI, display elapsed, min, max, sdev for each thread

## SEE ALSO

[**latency-plot**(1)](/latency-plot/1.md), [**latency-test**(1)](/latency-test/1.md), [**linuxcnc**(1)](/linuxcnc/1.md)

Much more information about LinuxCNC and HAL is available in the LinuxCNC and HAL User Manuals, found at */usr/share/doc/linuxcnc/*.

## BUGS

None known at this time.

## AUTHOR

This man page written by andypugh, as part of the LinuxCNC project.

## REPORTING BUGS

Report bugs at https://github.com/LinuxCNC/linuxcnc/issues

## COPYRIGHT

Copyright © 2020 andypugh.\
 This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.