A problem in which data cannot be output in real time during serial communication between NodeMCU and PC

Question

Environment: ubuntu18.04, python3.7, Arduino IDE(Linux 64bit), vsCode.

2loadcells_namedPipe.ino

#include <Arduino.h>
#include "HX711.h"

const int LOADCELL_DOUT_PIN = 4, LOADCELL_SCK_PIN = 5;
const int LOADCELL_DOUT_PIN2 = 12, LOADCELL_SCK_PIN2 = 13;

HX711 scale, scale2;

void setup() {
    Serial.begin(115200); // 9600이면 1초에 900bytes 정도 전송 가능.
    scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
    scale2.begin(LOADCELL_DOUT_PIN2, LOADCELL_SCK_PIN2);
    
    scale.set_scale();
    scale2.set_scale();

//    Serial.println("Tare. remove any weights");
//    delay(500);
    scale.tare();
    scale2.tare();
    Serial.println("Tare done");
}

void loop() {
  if (scale.is_ready() && scale2.is_ready()){
    long reading = scale.get_units(10);
    long reading2= scale2.get_units(10);

    Serial.println((String) reading + ", " + reading2); // (String) 없애면 알아볼 수 없는 값 나옴.
  }
  else{
    Serial.println("hx711 connect error");
  }
  delay(100); // 시간이 길어지면 receiver에서 출력되는 값이 더 많아짐. 
              // 시리얼통신이기 때문에 직렬로 입력되는 data가 너무 빨리 들어가면 named pipe가 출력할 때 
              // 과부하가 걸려서 자동 종료되는 원리?
}

sender.py

import serial
import time
import os.path

# NodeMCU=serial.Serial(port="/dev/ttyACM0", baudrate=115200)
NodeMCU = serial.Serial('/dev/ttyACM0', 115200)
time.sleep(3)  # 초기화 완료될 시간 약간 기다리기.

FIFO_FILENAME = './fifo-test'
if not os.path.exists(FIFO_FILENAME):
    os.mkfifo(FIFO_FILENAME)

if os.path.exists(FIFO_FILENAME):
    fp_fifo = open(FIFO_FILENAME, "w")
    data = ''
    fp_fifo.write(data)

    while True:
        c = NodeMCU.readline() # readlines()로 하면 입력이 끝났을 때까지 한 번에 읽어와서 무한루프로 input data 읽어오는 경우 출력 안 됨.
        data = c.decode()
        fp_fifo.write(data)

receiver.py

import os.path

FIFO_FILENAME = './fifo-test'

if os.path.exists(FIFO_FILENAME):
    fp_fifo = open(FIFO_FILENAME, "r")
    i = 0
    while True:
        with open(FIFO_FILENAME, 'r') as fifo:
            data = fifo.read()
            line = data.split('\n') # 없애고 바로 print(data)하면 시리얼모니터에서 보이는 모습 그대로 출력 됨.
            for str in line:
                i = i+1
                print(str + "%4d" % i)

Output(receiver's terminal window)

-48, -236   1
-48, -72   2
-39, -221   3
-13, -271   4
-42, -186   5
-40, -31   6
-47, 21   7
-21, -247   8
-6, -134   9
-1, -20  10
-5, -110  11
-59, -32  12
-35, -32  13
-4, -62  14
13, -21  15
  16

Error message:

somin@laptop:~/Desktop/2loadcells_namedPipe$ python sender.py 
Traceback (most recent call last):
  File "sender.py", line 19, in <module>
    c = NodeMCU.readline() # readlines()로 하면 입력이 끝났을 때까지 한 번에 읽어와서 무한루프로 input data 읽어오는 경우 출력 안 됨.
  File "/home/somin/.local/lib/python3.7/site-packages/serial/serialposix.py", line 596, in read
    'device reports readiness to read but returned no data '
serial.serialutil.SerialException: device reports readiness to read but returned no data (device disconnected or multiple access on port?)

Expected:

The sender continues to run without being terminated, and the receiver continues to output input data.

Of existing question:
Python SerialException: Device reports readiness to read but returned no data (device disconnected?)
: It seems to be a different problem when I see that it is input correctly when debugging.

results of several trials:
But when I debugged it, several datas came in(what I want!)
Create and remove fifo file every time data is read