CPU Usage Profiler Example

Source code path: example/system/cpu_usage_profiler

Supported Platforms

  • sf32lb52-lcd_n16r8

Overview

This example demonstrates the configuration and usage of cpu_usage_profiler, with features including:

  • CPU usage statistics: idle time (idle_run_time), non-idle time (other_run_time), CPU usage rate (default 2s statistics once).

  • Thread switching history records. Records the thread name and switching time for each thread switch.

  • Interrupt history records. Records the interrupt number and interrupt trigger time.

  • CPU Usage Metrics. Records CPU idle time (idle time), non-idle time (other run time), thread run time (thread run time). Supports:

    • Periodic printing.

    • Collection and storage through Metrics Collector functionality.

Tip

  • The time for thread switching and interrupt records is calculated based on GTIMER boot time (seconds/microseconds).

  • The statistical information of CPU Usage Metrics is cleared and restarted after each collection or printing.

Example Usage

Hardware Requirements

Before running this example, you need to prepare a development board supported by this example.

Compilation and Flashing

Switch to the example project directory and run the scons command to compile:

scons --board=sf32lb52-lcd_n16r8 -j32

Run build_sf32lb52-lcd_n16r8_hcpu\uart_download.bat, select the port as prompted for download:

$ ./uart_download.bat

     Uart Download

please input the serial port num:5

For detailed steps on compilation and download, please refer to the relevant introduction in Getting Started Guide.

Expected Results

  1. Thread switching history is saved in thread_switch_hist, interrupt history records are saved in isr_hist, which can be viewed through online or offline means such as ozone\T32. For example, when an exception occurs, you can easily see the thread switching records through T32: t32_switch_hist

  2. When CPU Usage Metrics is configured as periodic printing, it will periodically print CPU Usage information (the printing period configured here is 10s):

    07-03 17:59:52:616    [328360] I/NO_TAG: ============================
07-03 17:59:52:625    [0m[328382] I/NO_TAG: CPU Usage:    9.93/   9.94 (   0.15%)
07-03 17:59:52:632    [0m[328411] I/NO_TAG: ========================================================
07-03 17:59:52:641    [0m[328442] I/NO_TAG: thread      run_time(s)    load(%)
07-03 17:59:52:648    [0m[328465] I/NO_TAG: --------------------------------------------------------
07-03 17:59:52:662    [0m[328496] I/NO_TAG: [tshell  ]:    0.01    0.15% 
07-03 17:59:52:672    [0m[328518] I/NO_TAG: [tidle   ]:    9.93   99.85% 
07-03 17:59:52:680    [0m[328540] I/NO_TAG: [timer   ]:    0.00    0.00% 
07-03 17:59:52:692    [0m[328562] I/NO_TAG: [main    ]:    0.00    0.00% 
07-03 17:59:52:813    [0m
07-03 18:00:02:607    [656066] I/NO_TAG: ============================
07-03 18:00:02:619    [0m[656087] I/NO_TAG: CPU Usage:    9.99/  10.00 (   0.07%)
07-03 18:00:02:627    [0m[656112] I/NO_TAG: ========================================================
07-03 18:00:02:637    [0m[656143] I/NO_TAG: thread      run_time(s)    load(%)
07-03 18:00:02:644    [0m[656166] I/NO_TAG: --------------------------------------------------------
07-03 18:00:02:653    [0m[656197] I/NO_TAG: [tshell  ]:    0.00    0.00% 
07-03 18:00:02:660    [0m[328218] I/NO_TAG: [tidle   ]:    9.99   99.93% 
07-03 18:00:02:670    [0m[328240] I/NO_TAG: [timer   ]:    0.01    0.07% 
07-03 18:00:02:678    [0m[328262] I/NO_TAG: [main    ]:    0.00    0.00%

  3. Supported FINSH commands:

    Command

    Description

    cpu_prof_init

    Initialize profiler functionality

    cpu_prof_deinit

    Cancel profiler functionality

    cpu_prof_reset

    Reset CPU statistics

    cpu

    Print CPU statistics (if CPU Usage Metrics is enabled, it will also print thread loads)

    The following is the cpu command print (here CPU Usage Metrics is enabled):

    07-03 23:35:53:806 TX:cpu
07-03 23:35:53:811    [1049619] I/NO_TAG: CPU usage: 0.33
07-03 23:35:53:814    
07-03 23:35:53:819    [0m[1049637] I/NO_TAG: ============================
07-03 23:35:53:822    [0m[1049659] I/NO_TAG: CPU Usage:    1.94/   1.95 (   0.34%)
07-03 23:35:53:828    [0m[1049684] I/NO_TAG: ========================================================
07-03 23:35:53:832    [0m[1049715] I/NO_TAG: thread      run_time(s)    load(%)
07-03 23:35:53:837    [0m[1049739] I/NO_TAG: --------------------------------------------------------
07-03 23:35:53:839    [0m[1049770] I/NO_TAG: [tshell  ]:    0.00    0.00% 
07-03 23:35:53:844    [0m[1049792] I/NO_TAG: [tidle   ]:    1.94   99.66% 
07-03 23:35:53:848    [0m[1049814] I/NO_TAG: [timer   ]:    0.01    0.34% 
07-03 23:35:53:852    [0m[1049836] I/NO_TAG: [main    ]:    0.00    0.00%

Exception Diagnosis

Reference Documentation

Update History

Version

Date

Release Notes

0.0.1

07/2025

Initial version