Flask+SQLite+Tornado 在 Windows 2019 下 100 并发都撑不住是怎么回事？

非常简易的一个测试程序

# -*- coding: UTF-8 -*- from flask import Flask, request import json import time import re import sys import asyncio from tornado.ioloop import IOLoop from tornado.wsgi import WSGIContainer from tornado.httpserver import HTTPServer import sqlalchemy from sqlalchemy.ext.declarative import declarative_base from sqlalchemy import Column, Integer, String, create_engine from sqlalchemy.orm import sessionmaker engine = create_engine('sqlite:///database.db?check_same_thread=False') Base = declarative_base() class ClientLog(Base): __tablename__ = 'clientlog' log_id = Column(Integer, primary_key=True, autoincrement=True) message = Column(String(512)) def __repr__(self): return "A" from sqlalchemy.ext.declarative import DeclarativeMeta class AlchemyEncoder(json.JSONEncoder): def default(self, obj): if isinstance(obj.__class__, DeclarativeMeta): # an SQLAlchemy class fields = {} for field in [x for x in dir(obj) if not x.startswith('_') and x != 'metadata']: data = obj.__getattribute__(field) try: json.dumps(data) # this will fail on non-encodable values, like other classes fields[field] = data except TypeError: fields[field] = None # a json-encodable dict return fields return json.JSONEncoder.default(self, obj) Base.metadata.create_all(engine, checkfirst=True) Session = sessionmaker(bind=engine) session = Session() app = Flask("app") @app.route('/api', methods=['GET', 'POST']) @app.route('/api/', methods=['GET', 'POST']) def api1(): session.add(ClientLog(message="test")) sesson.commit() return "test" def launch_server(): if sys.platform == 'win32': asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy()) http_server = HTTPServer(WSGIContainer(app)) http_server.listen(8080) IOLoop.current().start() launch_server() 

在阿里云的 Windows 2019 模板下 100 并发就会崩溃退出，报错

Exception in thread Tornado selector: Traceback (most recent call last): File "C:\Users\Administrator\AppData\Local\Programs\Python\Python311\Lib\threading.py", line 1045, in _bootstrap_inner self.run() File "C:\Users\Administrator\AppData\Local\Programs\Python\Python311\Lib\threading.py", line 982, in run self._target(*self._args, **self._kwargs) File "C:\Users\Administrator\AppData\Local\Programs\Python\Python311\Lib\site-packages\tornado\platform\asyncio.py", line 574, in _run_select rs, ws, xs = select.select(to_read, to_write, to_write) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ValueError: too many file descriptors in select() 

但是我在 Windows 10 的电脑上测试并发没问题 之前测试换了另外一个对 Windows 更友好的 web framework （想不起来名字，找了半天没找到）可以是可以，但是估计它用了不止一个进程写 SQLite ，导致冲突无法提交更改 业务需求调用一个 Windows Only 的 pip 包 ，无法更换 Linux 服务器