client.get(buff) causes freeMemory to drop significantly, .stop() doesn't release

[JEG8]

Hi,

I am facing an issue with the library (in conjunction with and ) via your OTASketchDownloadWifi example, where I make a very simple call of client.get(buff), where buff is defined as the path for my server. My freeMemory (between heap and stack) drops by 1.5K when this call happens. I am assuming the memory is being claimed by something in the ArduinoHttpClient library. When I call client.stop(), the memory is not released. This makes it very difficult to use in a system where memory is critical.

Is there any reason why this would happen? Is there a recommended method to prevent this drop or does your library provide a way to fix this?

Thanks for any help in advance.

[JAndrassy]

is it not some glitch in the code for the free memory calculation?

[JEG8]

No, it is directly from MemoryFree library. https://github.com/mpflaga/Arduino-MemoryFree/blob/master/MemoryFree.cpp

[JAndrassy]

I used that too so I know it is OK. Once I had some other and it didn't work good.

Is the buff string terminated by 0?

[JEG8]

Yes, the buff string is being formulated using the code below. snprintf properly adds the null terminator to the string. I printed out the hex contents and did in fact see that the null terminator.

char buff[32];
  snprintf(buff, sizeof(buff), PATH);

Also, if I comment out the client.get() call, the memory usage does not drop. It doesn't seem like its in the formation of the object, but instead the .get() call itself.

[JAndrassy]

The WiFiNINA library allocates 1500 bytes for buffers at once, but only once.

https://github.com/arduino-libraries/WiFiNINA/blob/12c33f10cc3eddad245a2263fe0476fee60320a2/src/utility/WiFiSocketBuffer.cpp#L60

[JEG8]

Great find! Thank you, this explains what I am seeing.

Do you know of any way I can save memory with this implementation?

[JAndrassy]

you can change the WIFI_SOCKET_BUFFER_SIZE at the beginning of WiFiSocketBuffer.cpp

[JEG8]

Thank you for your help! I will mark this issue as closed.