BLE Log Compression Scheme (Preview)
一、Overview
This scheme scans the code of BLE stack-related components during the compilation phase, converting formatted strings and parameters in log statements into pure binary data. This improves log output efficiency and reduces the Flash footprint of the protocol stack.
Currently, the scheme supports log compression for both BLE-MESH and BLE-HOST-BLUEDROID components.
二、How to Use
This feature requires additional Python libraries. Please follow the steps below to set up the environment.
Step 1: Verify ESP-IDF Virtual Environment
Ensure all subsequent steps are performed within the ESP-IDF Python virtual environment.
Verify activation by running:
idf.py --version
If the output shows idf.py: command not found, the virtual environment is not active.
Refer to the official documentation to configure and activate the environment: ESP-IDF Setup Guide
After activation, run idf.py --version again. A version number confirms successful setup.
Step 2: Check Python Version
Within the virtual environment, check the Python version:
python --version
If the version is lower than 3.8, upgrade Python by following the same official guide: Python Upgrade Guide
Step 3: Install Log Compression Dependencies
Choose the appropriate command below based on your operating system and terminal environment to install the required dependencies: If you are using Linux or macos, please use the following command:
- Linux or macOS:
pip install -r $IDF_PATH/components/bt/common/ble_log/log_compression/scripts/requirements.txt - Windows (PowerShell):
pip install -r $Env:IDF_PATH\components\bt\common\ble_log\log_compression\scripts\requirements.txt - Windows (Command Prompt - Cmd):
pip install -r %IDF_PATH%\components\bt\common\ble_log\log_compression\scripts\requirements.txt
Step 4: Clean Build Cache
After installing the dependencies, it is recommended to delete the existing build folder (if any) and rebuild the application to ensure a clean environment.
Step 5: Configure via Menuconfig
Run idf.py menuconfig and navigate to the following path to enable BLE-MESH log compression:
(Top) -> Component config -> Bluetooth -> Common Options -> BLE Log -> Enable BLE log compression(Preview, Please read help information)->Enable BLE Mesh log compression(Preview).
There are three configuration items under this submenu:
-
Mesh log buffer length: Sets the maximum length of a single log entry.
-
Maximum number of tasks that can generate BLE mesh logs: Sets the maximum number of tasks that can output BLE-MESH logs (the default is recommended; avoid modifying this).
Step 6: Build the Application
After configuration, build the application with:
idf.py build
Watch for any warnings during the build process. For example:
CMake Warning at esp/esp-idf/components/bt/common/ble_log/log_compression/CMakeLists.txt:46 (message):
tree_sitter import failed, please check whether the package is installed
correctly,Please refer to the
file: esp/esp-idf/components/bt/common/ble_log/log_compression/README
for installation instructions.
This indicates that the dependencies were not installed correctly, and log compression has failed—falling back to a normal build. Please repeat Steps 1–4.
If log compression is successful, you will see output similar to:
[0/1285] Log compression is being performed, please wait...
Log compression underway, please wait...
Found module BLE_MESH for compression
Found 111 source files in module BLE_MESH requiring compression
3055 ble log(s) compressed
Header file for compressed logs generated
After a successful build, the following structure will be generated under build/ble_log/:
build/ble_log/
├── ble_log_database
│ └── BLE_MESH_logs.json
├── ble_script_log_{timestamp}.log
├── .compressed_srcs
│ └── esp_ble_mesh
├── include
│ └── mesh_log_index.h
└── module_info.yml
.compressed_srcs: Compressed C source files.mesh_log_index.h: Generated header file containing log macros.BLE_MESH_logs.json: Detailed information for each log entry.ble_script_log_{timestamp}.log: Log generated by the compression script.module_info.yml: Configuration file for compressed logging across modules.
Do not modify these auto-generated files.
Step 7: Receive Logs
With log compression enabled and under the default configuration, all log levels except ERR and WARN generated by the compressed component will be redirected to the compression-log interface for output. Please refer to the BLE Log module’s documentation for how to receive these logs: BLE Log module.
Frequently Asked Questions
- If encoded logs cause compilation errors or missing macro definitions, delete the build folder and rebuild. If the issue persists, please report it to the Espressif BLE team.