详细可看链接:https://mp.weixin.qq.com/s/eC599TS_0kfwDK4LGgPa1g

    1. galaxy@DESKTOP-65O8NBN:/mnt/c/Users/Mechrevo$ ulimit -a
    2. core file size (blocks, -c) 0
    3. data seg size (kbytes, -d) unlimited
    4. scheduling priority (-e) 0
    5. file size (blocks, -f) unlimited
    6. pending signals (-i) 7823
    7. max locked memory (kbytes, -l) 64
    8. max memory size (kbytes, -m) unlimited
    9. open files (-n) 1024
    10. pipe size (512 bytes, -p) 8
    11. POSIX message queues (bytes, -q) 819200
    12. real-time priority (-r) 0
    13. stack size (kbytes, -s) 8192
    14. cpu time (seconds, -t) unlimited
    15. max user processes (-u) 7823
    16. virtual memory (kbytes, -v) unlimited
    17. file locks (-x) unlimited

    可以看到stack size是8M,他是进程创建线程时为线程默认分配的栈空间大小,并且这个stack是用户态的栈。
    main线程的栈大小是大于8M的,但是其他的线程的线程栈大小就是stack size固定的大小,就是8M。