多线程 cv2.resize 内存泄露, 求指点

[iteye_7771]

现象:
循环 1W以上, 发现python进程内存持续上涨, res非常高. 代码未看出问题, 求指点
每次循环时, ThreadPoolExecutor 都是一个新对象

代码如下:

import requests
import cv2
import time
import os
import sys
from concurrent.futures import ThreadPoolExecutor, wait
from datetime import datetime

timeout_second = 1
tmp_jpg = "tmp_jpg"
if not os.path.exists(tmp_jpg):
    os.mkdir(tmp_jpg)

req = requests.get("https://img14.360buyimg.com/babel/s1180x940_jfs/t1/169636/37/9236/297058/6040a6beEce62815f/d5a845163b127dd5.jpg")
file_path = "./" + tmp_jpg + "/target_file" 
open(file_path, 'wb').write(req.content)

def get_pic_by_ur():
    try:
        item_tmp_img = file_path
        img = cv2.imread(item_tmp_img)
        cv2.resize(img, (300, 300))
    except Exception as e:
        print("error, need_exist")
        sys.exit(-1)
    finally:
        pass
    
    
c = 0
thread_count = 20
if len(sys.argv) == 2:
    thread_count = int(sys.argv[1])
print("thread_count = " + str(thread_count))
time.sleep(3)
while True:
    executor = ThreadPoolExecutor(thread_count, thread_name_prefix="process_image_")
    result_list = []
    for i in range(thread_count):
        result = executor.submit(get_pic_by_ur)
        result_list.append(result)
    wait(result_list)
    executor.shutdown(wait=True)

    c = c + 1
    if c % 100 == 0:
        print(str(datetime.now()) + "," + str(c))