How does debugger's Heap Usage (FreeRTOS) tab work?

[kackle123]

Looking at the MCUXpresso screen shot, I have a 125 kB FreeRTOS heap.  The tab's graphic says it's fine, but the tab's list seems to show that it's all used up if I add up the numbers.  Am I reading it incorrectly? 

Also, what does "Allocated" mean when that particular memory block is NOT designated to  FreeRTOS task like the others?

[kackle123]

Hi Edwin,

It is a Kinetis K64 MCU (MK64FN1M0VLQ12).  The MCUXpresso is version 11.6.  The SDK, v2.11.0 and manifest v3.9.0.

[EdwinHz]

Hi @kackle123,

Thanks for the clarification. You are reading the tab's list correctly; I believe there might be a bug or error with the graphic instead. That said, the IDE version that you are using is about two years old by now, and many improvements have been made to the FreeRTOS related windows. Please update to the latest MCUXpresso IDE (Currently v24.9) and try again.

BR,
Edwin.

[kackle123]

How can the FreeRTOS dynamic memory allocator give out more than 135 kB if the heap was only configured for 125 kB (configTOTAL_HEAP_SIZE)?

Repeating my second question: What does "Allocated" mean when that particular memory block is NOT designated to FreeRTOS task like the others?

[EdwinHz · Accepted solution]

Hi @kackle123,

1. It can't, this is why I mention that it is probably a bug. Please try updating to the latest IDE version and try again.

2. FreeRTOS also requires heap resources besides the ones reserved for each task, this is why there are some sections that are marked as "Allocated".

BR,
Edwin.

[kackle123]

As far as updating the IDE, I may not be able to do that until the project is complete (very soon).

The declared allocations explanations make sense.  Thank you for your replies.

[EdwinHz]

Hi @kackle123,

Could you share what MCU are you using? Also, the IDE and SDK versions that you are currently working with.

BR,
Edwin. 

[kackle123]

(Sorry, I replied in the wrong place.)

Hi Edwin,

It is a Kinetis K64 MCU (MK64FN1M0VLQ12).  The MCUXpresso is version 11.6.  The SDK, v2.11.0 and manifest v3.9.0.