stack overflow是函数调用次数过多吗？

Question

如果是，那为什么sys.setrecursionlimit(999999)后仍然是这个报错？

m=999999
import sys
sys.setrecursionlimit(999999)
def calculate():
    global m
    while str(m)[-1:1:-1]==str(m)[2::1]:

        while str(m-1)[1::1]==str(m-1)[-1:0:-1]:
            while str(m-2)[1:-1]==str(m-2)[-2:0:-1]:
                while str(m-3)!=str(m-3)[::-1]:
                    m=m-1
                else:
                    return m
                print(m)


        else:
            m=m-1
    else:
        m=m-1
        calculate()
calculate()

报错信息：
Traceback (most recent call last):
File "C:\Users\jyz_1\Desktop\mile.py", line 22, in
calculate()
File "C:\Users\jyz_1\Desktop\mile.py", line 21, in calculate
calculate()
File "C:\Users\jyz_1\Desktop\mile.py", line 21, in calculate
calculate()
File "C:\Users\jyz_1\Desktop\mile.py", line 21, in calculate
calculate()
[Previous line repeated 6779 more times]
File "C:\Users\jyz_1\Desktop\mile.py", line 6, in calculate
while str(m)[-1:1:-1]==str(m)[2::1]:
MemoryError: stack overflow

Answer 1

递归深度过大，比如说calculate()一直调用else，calculate()