esp32-c3: run uasyncio in thread: maximum recursion depth?

[straga]

1. If runs without thread all right.
2. If run in thread: maximum recursion depth exceeded.

The same code is for ESP32 and STM32.

How depth maybe call one function from others?

[fivdi]

Running this program on a ESP32-C3 shows that the maximum recursion depth is about 25.

def doit(count):
    print(count)
    doit(count + 1)

doit(1)

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Traceback (most recent call last):
  File "<stdin>", line 5, in <module>
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 3, in doit
  File "<stdin>", line 2, in doit
RuntimeError: maximum recursion depth exceeded

If a thread is used the maximum recursion depth is about 6.

import utime
import _thread

def doit(count):
    print(count)
    doit(count + 1)

def my_thread():
    doit(1)

_thread.start_new_thread(my_thread, ())

while True:
    utime.sleep(1)

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Unhandled exception in thread started by <function my_thread at 0x3fca09c0>
Traceback (most recent call last):
  File "<stdin>", line 9, in my_thread
  File "<stdin>", line 6, in doit
  File "<stdin>", line 6, in doit
  File "<stdin>", line 6, in doit
  File "<stdin>", line 6, in doit
  File "<stdin>", line 6, in doit
  File "<stdin>", line 6, in doit
  File "<stdin>", line 5, in doit
RuntimeError: maximum recursion depth exceeded

if _thread.stack_size(1024 * 16) is called to increase the stack size for threads to 16 kilobytes, the maximum recursion depth is about 28.

import utime
import _thread

_thread.stack_size(1024 * 16)

def doit(count):
    print(count)
    doit(count + 1)

def my_thread():
    doit(1)

_thread.start_new_thread(my_thread, ())

while True:
    utime.sleep(1)

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Unhandled exception in thread started by <function my_thread at 0x3fca09c0>
Traceback (most recent call last):
  File "<stdin>", line 11, in my_thread
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 8, in doit
  File "<stdin>", line 7, in doit
RuntimeError: maximum recursion depth exceeded

This means it should be possible to resolved the issue by calling _thread.stack_size() with the appropriate stack size.

[straga]

Thanks for the information. I grow the stack size to 16.