Memory usage monitoring in FreeRTOS - Mini Project: Build & Apply

Memory Usage Monitoring in FreeRTOS

📖 Scenario: You are working on an embedded system using FreeRTOS. To ensure your system runs smoothly, you need to monitor the memory usage of your tasks. This helps prevent crashes caused by running out of memory.

🎯 Goal: Build a simple FreeRTOS program that tracks the free heap memory available and prints it periodically. You will create a variable to hold the heap size, configure a monitoring interval, write the code to get the free heap size, and finally print the result.

📋 What You'll Learn

Create a variable to store the free heap size

Add a configuration variable for the monitoring interval in milliseconds

Use the FreeRTOS API to get the current free heap size

Print the free heap size to the console

💡 Why This Matters

🌍 Real World

Monitoring memory usage helps embedded developers avoid crashes and optimize resource use in devices like IoT sensors, wearables, and controllers.

💼 Career

Understanding how to monitor and manage memory in FreeRTOS is essential for embedded systems engineers and firmware developers to ensure system reliability.

1

Create a variable to store free heap size

Create a variable called freeHeapSize of type size_t and initialize it to 0.

FreeRTOS

# Create a variable called freeHeapSize of type size_t and initialize it to 0
// Your code here

Need a hint?

Use size_t for memory size variables in FreeRTOS.

2

Add a configuration variable for monitoring interval

Add a variable called monitorIntervalMs of type const TickType_t and set it to 1000 to represent 1000 milliseconds (1 second).

FreeRTOS

size_t freeHeapSize = 0;
// Add a variable called monitorIntervalMs of type const TickType_t set to 1000
// Your code here

Need a hint?

Use const TickType_t for fixed time intervals in FreeRTOS.

3

Get the current free heap size

Use the FreeRTOS API function xPortGetFreeHeapSize() to assign the current free heap size to the variable freeHeapSize.

FreeRTOS

size_t freeHeapSize = 0;
const TickType_t monitorIntervalMs = 1000;
// Assign freeHeapSize using xPortGetFreeHeapSize()
// Your code here

Need a hint?

Call xPortGetFreeHeapSize() without parameters to get free heap size.

4

Print the free heap size

Write a printf statement to display the text "Free heap size: " followed by the value of freeHeapSize and a newline.

FreeRTOS

size_t freeHeapSize = 0;
const TickType_t monitorIntervalMs = 1000;
freeHeapSize = xPortGetFreeHeapSize();
// Print the free heap size
// Your code here

Need a hint?

Use printf("Free heap size: %u\n", (unsigned int)freeHeapSize); to print the value.