MCUXpresso IDE中的主题 Analyze Heap size

Analyze Heap size

hiroshihiraga — Tue, 18 Aug 2020 08:11:48 GMT

Hi,

Is it possible to analyze a heap size?

I know that there is a feature of FreeRTOS heap size monitoring.

Standard C library malloc or even sprintf uses heap memory that is not managed region of memory by RTOS.

I think such standard C library is not recommended to use when RTOS is used due to non thread safe. But, some customers still want to use such C standard library and analyze the heap size.

Hiroshi,

Re: Analyze Heap size

jingpan — Wed, 19 Aug 2020 03:04:31 GMT

Hi Hiroshi,

MCUxpresso IDE has tools for FreeRTOS HEAP usage monitor. This is the easiest way.

FreeRTOS itself hasn't such a library. There is some discuss on internet about how to monitor. People have to write monitor code by themselves.

Regards,

Jing

Re: Analyze Heap size

hiroshihiraga — Wed, 19 Aug 2020 06:44:01 GMT

HI, jingpan‌

Thanks, ok. I will look up the internet.

And, don't you have any information about monitoring the heap size that is not managed by RTOS?

Hiroshi,

Re: Analyze Heap size

converse — Wed, 19 Aug 2020 07:41:42 GMT

Mixing heaps (C library and FreeRTOS) is not a good idea and could lead to some very hardtop-debug issues. However, if you insist, then see

Heap allocation/checking in Redlib

and the final reply here

https://community.nxp.com/thread/521689

Re: Analyze Heap size

danielholala — Mon, 20 Dec 2021 10:05:01 GMT

How do you avoid mixing heaps in case you want to use FreeRTOS and C library functions when some of them use malloc() and free()?

I see at least to possible approaches:

Redirect malloc() and free() to their FreeRTOS equivalents defined in one of the heap memory schemes

Define the stubs needed for malloc/free to work (e.g., sbrk(), ...) and implement FreeRTOS pvPortMalloc() and vPortFree() by using malloc()/free()

The latter is Dave Nadler's approach.

Maybe you suggest a different third approach?

Thanks!
Dan

Re: Analyze Heap size

danielholala — Wed, 22 Dec 2021 08:38:23 GMT

Ups, have to reply to myself.

I read that Dave Nadler already tried the first approach and stopped after he figured that FreeRTOS heap implementations would not support realloc()directly. One would have to implement this function.

So I guess the easiest way is to redirect pvPortMalloc() and vPortFree() using D. Nadler's code. However, with this approach, one forfeits the use of Heap View in MCUXpresso IDE.