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Merge pull request #3097 from smoe/install_docs_changes
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docs: translation-triggered changes on latency-test (smoe:install_docs_changes)
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petterreinholdtsen authored Aug 31, 2024
2 parents 53d9441 + f486120 commit 69feb3b
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55 changes: 27 additions & 28 deletions docs/src/install/latency-test.adoc
Original file line number Diff line number Diff line change
Expand Up @@ -32,8 +32,6 @@ However, software step pulses also have some disadvantages:
- loads the CPU




[[sec:latency-tests]]
== Latency Tests(((Latency Tests)))

Expand All @@ -55,16 +53,16 @@ and run the following command:
latency-test
----

This will start the latency test with a base-thread period of 25uS and a
servo-thread period of 1mS. The period times may be specified on the command
This will start the latency test with a base-thread period of 25 µs and a
servo-thread period of 1 ms. The period times may be specified on the command
line:

----
latency-test 50000 1000000
----

This will start the latency test with a base-thread period of 50uS and a
servo-thread period of 1mS.
servo-thread period of 1 ms.

For available options, on the command line enter:

Expand Down Expand Up @@ -93,18 +91,18 @@ You should run the test for at least several minutes; sometimes
the worst case latency doesn't happen very often, or only happens
when you do some particular action. For instance, one Intel
motherboard worked pretty well most of the time, but every 64
seconds it had a very bad 300 us latency. Fortunately that was
fixable, see https://wiki.linuxcnc.org/cgi-bin/wiki.pl?FixingSMIIssues
seconds it had a very bad 300 µs latency. Fortunately that was
fixable, see https://wiki.linuxcnc.org/cgi-bin/wiki.pl?FixingSMIIssues .

So, what do the results mean? If your Max Jitter number is less
than about 15-20 microseconds (15000-20000 nanoseconds), the
computer should give very nice results with software stepping. If
the max latency is more like 30-50 microseconds, you can still
computer should give very nice results with software stepping.
If the max latency is more like 30-50 microseconds, you can still
get good results, but your maximum step rate might be a little
disappointing, especially if you use microstepping or have very
fine pitch leadscrews. If the numbers are 100 us or more (100,000
nanoseconds), then the PC is not a good candidate for software
stepping. Numbers over 1 millisecond (1,000,000 nanoseconds) mean
fine pitch leadscrews. If the numbers are 100 µs or more,
i.e. >= 100,000 nanoseconds (ns), then the PC is not a good candidate for software
stepping. Numbers over 1 millisecond (1,000,000 ns) mean
the PC is not a good candidate for LinuxCNC, regardless of whether you
use software stepping or not.

Expand All @@ -117,8 +115,9 @@ LinuxCNC does not require bleeding edge hardware.
For more information on stepper tuning see the
<<cha:stepper-tuning,Stepper Tuning>> Chapter.

*Additional command line tools are available for examining latency
when LinuxCNC is not running.*
[TIP]
Additional command line tools are available for examining latency
when LinuxCNC is not running.

=== Latency Plot

Expand All @@ -134,9 +133,9 @@ Usage:
latency-plot --hal [Options]
Options:
--base nS (base thread interval, default: 25000)
--servo nS (servo thread interval, default: 1000000)
--time mS (report interval, default: 1000)
--base ns (base thread interval in nanoseconds, default: 25000)
--servo ns (servo thread interval in nanoseconds, default: 1000000)
--time ms (report interval in milliseconds, default: 1000)
--relative (relative clock time (default))
--actual (actual clock time)
----
Expand All @@ -147,7 +146,7 @@ image::../config/images/latency-plot.png["latency-plot Window"]

=== Latency Histogram

latency-histogram displays a histogram of latency (jitter) for
The application latency-histogram displays a histogram of latency (jitter) for
a base and servo thread.

----
Expand All @@ -156,10 +155,10 @@ Usage:
latency-histogram [Options]
Options:
--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
--base ns (base thread interval in nanoseconds, default: 25000, min: 5000)
--servo ns (servo thread interval in nanoseconds, default: 1000000, min: 25000)
--bbinsize ns (base bin size in nanoseconds, default: 100
--sbinsize ns (servo bin size in nanoseconds, default: 100
--bbins n (base bins, default: 200
--sbins n (servo bins, default: 200
--logscale 0|1 (y axis log scale, default: 1)
Expand All @@ -170,12 +169,12 @@ Options:
--nox (no gui, display elapsed,min,max,sdev for each thread)
Notes:
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] bin
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] bin
----

.`latency-histogram` Window
Expand Down

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