# Non-linear pressure advance

**URL:** <https://klipper.discourse.group/t/non-linear-pressure-advance/24699>\
**Category:** Developers\
**Created:** [August 28, 2025, 7:38pm UTC](https://klipper.discourse.group/t/non-linear-pressure-advance/24699 "2025-08-28T19:38:00Z")\
**Posts on this page:** 1\
**Showing post:** 2

<div class="post-metadata">

**Author:** ![nefelim4ag](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/nefelim4ag/32/2387_2.png) [@nefelim4ag](https://klipper.discourse.group/u/nefelim4ag)\
**Post date:** [August 29, 2025, 12:38am UTC](https://klipper.discourse.group/t/non-linear-pressure-advance/24699/2 "2025-08-29T00:38:11Z")

</div>

General comments:

- It is preferable to do iterative changes, piece by piece.
- Do not mix the refactoring with functional changes.

_It is harder to grasp. Just imagine, if Kevin, for example, with comparable changes in the raw line count, just squashes it: [Centralize host motion flushing by KevinOConnor · Pull Request #7014 · Klipper3d/klipper · GitHub](https://github.com/Klipper3d/klipper/pull/7014/files)_  
_This is a part of the task: write commits and change the code in a way that would be readable to others._

About the motion subsystem, general rule - there should be no speed jumps or infinite something. This is part of the reason why there is an integration logic - to smooth.

About the performance, I would suggest you do the testing with the Klipper batch mode:  
At least like that:

```auto
# It is enough to disable not used things, make a dummy MCU dict (just compile your MCU)
# Also set G28 at the start of the file, or SET_POSITION...
time python3 klippy/klippy.py rp2040_printer.cfg -a /tmp/klippy_uds -i ./Cube_0.1mm_PLA_19m36s.gcode -d out/klipper.dict -o /tmp/dummy.serial

```

That will give you a rough idea of how fast/slow it is.

About the testing, you can take a look at:

> **[Debugging - Klipper documentation](https://www.klipper3d.org/Debugging.html#motion-analysis-and-data-logging)**

```auto
# Record the data:
./scripts/motan/data_logger.py ~/printer_data/comms/klippy.sock /tmp/stepcompress_patched
# View the data:
./scripts/motan/motan_graph.py -g '[["deviation(angle(mt6826s),stepq(stepper_x))"],["deviation(angle(mt6826s),kin(stepper_x))"],["adxl345(adxl345,x)"],["adxl345(adxl345,y)"],["derivative(stepq(stepper_x))"],["step_phase(tmc5160 stepper_x)"]]' ./stepcompress_patched -s 0 -d 10

```

Also, it could help you:

- [Modification of Pressure Advance for high speed Bowden printers - #13 by dmbutyugin](https://klipper.discourse.group/t/modification-of-pressure-advance-for-high-speed-bowden-printers/13053/13)
- [Pressure\_advance\_smooth\_time skews pressure\_advance](https://klipper.discourse.group/t/pressure-advance-smooth-time-skews-pressure-advance/13451)  
(Generally, there is code somewhere, as in the above case for PA simulations).

Hope that helps.

---

_[View the full topic](https://klipper.discourse.group/t/non-linear-pressure-advance/24699)._