zephyr/samples/basic/minimal
Gerard Marull-Paretas 93b63df762 samples, tests: convert string-based twister lists to YAML lists
Twister now supports using YAML lists for all fields that were written
as space-separated lists. Used twister_to_list.py script. Some artifacts
on string length are due to how ruamel dumps content.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2023-05-10 09:52:37 +02:00
..
src samples, tests, boards: Switch main return type from void to int 2023-04-14 07:49:41 +09:00
CMakeLists.txt cmake: increase minimal required version to 3.20.0 2021-08-20 09:47:34 +02:00
README.rst samples: minimal: cleanups 2020-05-13 19:51:01 +02:00
arm.conf
common.conf samples: basic: minimal: remove pinmux 2022-06-06 15:39:50 -07:00
mt.conf
no-mt.conf samples: basic/minimal: disable memory pool when MT=n 2020-09-19 05:49:13 -04:00
no-preempt.conf
no-timers.conf
prj.conf samples: minimal: define an empty project configuration 2023-03-28 15:05:01 +02:00
sample.yaml samples, tests: convert string-based twister lists to YAML lists 2023-05-10 09:52:37 +02:00
x86.conf

README.rst

.. _minimal_sample:

Minimal footprint
#################

Overview
********

This sample provides an empty ``main()`` and various configuration files that
can be used to measure Zephyr's minimal ROM footprint in different
configurations.

The following configuration files are available:

* :file:`mt.conf`: Enable multithreading
* :file:`no-mt.conf`: Disable multithreading
* :file:`no-preempt.conf`: Disable preemption
* :file:`no-timers.conf`: Disable timers
* :file:`arm.conf`: Arm-specific disabling of features

Building and measuring ROM size
*******************************

The following combinations are suggested for comparing ROM sizes in different
configurations. They all target the :ref:`reel_board` (Arm Aarch32 architecture).

* Multithreading enabled

  * Reference ROM size: 7-8KB

  .. zephyr-app-commands::
     :zephyr-app: samples/basic/minimal
     :host-os: unix
     :board: reel_board
     :build-dir: reel_board/mt/
     :conf: "common.conf mt.conf arm.conf"
     :goals: rom_report
     :compact:

* Multithreading enabled, no preemption

  * Reference ROM size: 7-8KB

  .. zephyr-app-commands::
     :zephyr-app: samples/basic/minimal
     :host-os: unix
     :board: reel_board
     :build-dir: reel_board/mt-no-preempt/
     :conf: "common.conf mt.conf no-preempt.conf arm.conf"
     :goals: rom_report
     :compact:

* Multithreading enabled, no preemption, timers disabled

  * Reference ROM size: 3-4KB

  .. zephyr-app-commands::
     :zephyr-app: samples/basic/minimal
     :host-os: unix
     :board: reel_board
     :build-dir: reel_board/mt-no-preempt-no-timers/
     :conf: "common.conf mt.conf no-preempt.conf no-timers.conf arm.conf"
     :goals: rom_report
     :compact:

* Multithreading disabled, timers enabled

  * Reference ROM size: 4-5KB

  .. zephyr-app-commands::
     :zephyr-app: samples/basic/minimal
     :host-os: unix
     :board: reel_board
     :build-dir: reel_board/no-mt/
     :conf: "common.conf no-mt.conf arm.conf"
     :goals: rom_report
     :compact:

* Multithreading disabled, timers disabled

  * Reference ROM size: 2-3KB

  .. zephyr-app-commands::
     :zephyr-app: samples/basic/minimal
     :host-os: unix
     :board: reel_board
     :build-dir: reel_board/no-mt-no-timers/
     :conf: "common.conf no-mt.conf no-timers.conf arm.conf"
     :goals: rom_report
     :compact: