gsexton
commented
5 days ago Looking at adafruit_connectionmanager(), I'm not understanding how this will work without a call to gc.collect()
try:
socket = self._get_connected_socket(
addr_info, host, port, timeout, is_ssl, ssl_context
)
self._register_connected_socket(key, socket)
return socket
except (MemoryError, OSError, RuntimeError):
# Could not get a new socket (or two, if SSL).
# If there are any available sockets, free them all and try again.
if self.available_socket_count:
self._free_sockets()
socket = self._get_connected_socket(
addr_info, host, port, timeout, is_ssl, ssl_context
)
self._register_connected_socket(key, socket)
return socket
# Re-raise exception if no sockets could be freed.
raise
justmobilize
dhalbert
I have a Raspberry Pi Pico W running CircuitPython 9.0.5. I'm using the current version (HEAD) of Adafruit_CircuitPython_Requests, and the current HEAD of Adafruit_CircuitPython_ConnectionManager. The application files are compiled using mpy-cross 9.0.5. The size of the .mpy files is approximately 22K bytes and code.py is about 9K bytes.
My application is a thermometer with a LCD display. I'm using a TMP102, and an Adafruit ST7789 240x320 display. The display shows the current temp and time. Temperature readings are taken once a second, averaged, and once a minute, the program does a POST request to place the temperature data into an InfluxDB on a remote host. I'm also using Adafruit_CircuitPython_NTP at startup to set the RTC. Finally, I'm making requests to the OpenWeather API. The OpenWeather API call is made once per 10 minutes. I ran into problems with SSL certificates. If I tried to make requests to more than one SSL site, I immediately ran out of memory. To work around that, I made a proxy for the OpenWeather API on the same server that hosts Influx. Also, I'm using a GoDaddy cert, so I load the GoDaddy CA certificate using this code:
so I'm only calling one SSL http host. The requests session is created:
This worked pretty well for a year or so using CircuitPython 8.x.
What's happening is that about 7 minutes after startup, I start getting memory errors.
About every other call results in a MemoryError. After some time, failures become more prevalent.
I added some dumps of gc value, and can see when I enter the loop there's some 60K bytes free. After the first http requests, free memory reduces to about 20 K Bytes:
After a MemoryError, it looks like:
You can see that AFTER a memory error, a great deal more of memory is freed. I've noticed that free memory and allocated memory are unchanged UNLESS I use the requests library. IOW, reading the TMP102 and updating the display DON'T change the free memory.
Observations
So what seems to be happening is that calling the API library to make a request consumes around 40 K Bytes. When an error occurs, around 30KB is freed giving about 50K bytes free. A subsequent call consumes around 30K bytes. The call after that fails with out of memory.
Does anyone have any ideas on how to work around this? I feel like trying to follow conventional memory reduction techniques is just going to be useless since evidence shows the requests library consuming most of it.