新手尝试用 aiohttp 写了个爬虫，但是目前因为 task 过多(超过 1000 个)，报错 Too many open files，请问如何解决呢？

完整代码

import time import asyncio import aiohttp from bs4 import BeautifulSoup as bs BASE_URL = "http://www.biqudu.com" TITLE2URL = dict() COnTENT= list() async def fetch(url, callback=None, **kwarags): headers = {'User-Agent':'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'} sem = asyncio.Semaphore(5) with (await sem): async with aiohttp.ClientSession() as session: async with session.get(url, headers=headers) as res: page = await res.text() if callback: callback(page, **kwarags) else: return page def parse_url(page): soup = bs(page, "lxml") dd_a_doc = soup.select("dd > a") for a_doc in dd_a_doc: article_page_url = a_doc['href'] article_title = a_doc.get_text() if article_page_url: TITLE2URL[article_title] = article_page_url def parse_body(page, **kwarags): title = kwarags.get('title', '') print("{}".format(title)) soup = bs(page, "lxml") content_doc = soup.find("div", id="content") content_text = content_doc.get_text().replace('readx();', '').replace(' ', "\r\n") cOntent= "%s\n%s\n\n" % (title, content_text) CONTENT.append(content) def main(): t0 = time.time() loop = asyncio.get_event_loop() loop.run_until_complete(fetch(BASE_URL+"/43_43074/", callback=parse_url)) tasks = [fetch(BASE_URL + page_url, callback=parse_body, title=title) for title, page_url in TITLE2URL.items()] loop.run_until_complete(asyncio.gather(*tasks[:500])) loop.close() elapsed = time.time() - t0 print("cost {}".format(elapsed)) if __name__ == "__main__": main() 

错误信息

Traceback (most recent call last): File "/usr/local/lib/python3.5/dist-packages/aiohttp/connector.py", line 797, in _wrap_create_connection return (yield from self._loop.create_connection(*args, **kwargs)) File "/usr/lib/python3.5/asyncio/base_events.py", line 695, in create_connection raise exceptions[0] File "/usr/lib/python3.5/asyncio/base_events.py", line 662, in create_connection sock = socket.socket(family=family, type=type, proto=proto) File "/usr/lib/python3.5/socket.py", line 134, in __init__ _socket.socket.__init__(self, family, type, proto, fileno) OSError: [Errno 24] Too many open files The above exception was the direct cause of the following exception: Traceback (most recent call last): File "/home/xsy/Workspace/Self/aiotest/aiotest.py", line 58, in <module> main() File "/home/xsy/Workspace/Self/aiotest/aiotest.py", line 52, in main loop.run_until_complete(asyncio.gather(*tasks[:500])) File "/usr/lib/python3.5/asyncio/base_events.py", line 387, in run_until_complete return future.result() File "/usr/lib/python3.5/asyncio/futures.py", line 274, in result raise self._exception File "/usr/lib/python3.5/asyncio/tasks.py", line 239, in _step result = coro.send(None) File "/home/xsy/Workspace/Self/aiotest/aiotest.py", line 18, in fetch async with session.get(url, headers=headers) as res: File "/usr/local/lib/python3.5/dist-packages/aiohttp/client.py", line 690, in __aenter__ self._resp = yield from self._coro File "/usr/local/lib/python3.5/dist-packages/aiohttp/client.py", line 267, in _request cOnn= yield from self._connector.connect(req) File "/usr/local/lib/python3.5/dist-packages/aiohttp/connector.py", line 402, in connect proto = yield from self._create_connection(req) File "/usr/local/lib/python3.5/dist-packages/aiohttp/connector.py", line 749, in _create_connection _, proto = yield from self._create_direct_connection(req) File "/usr/local/lib/python3.5/dist-packages/aiohttp/connector.py", line 860, in _create_direct_connection raise last_exc File "/usr/local/lib/python3.5/dist-packages/aiohttp/connector.py", line 832, in _create_direct_connection req=req, client_error=client_error) File "/usr/local/lib/python3.5/dist-packages/aiohttp/connector.py", line 804, in _wrap_create_connection raise client_error(req.connection_key, exc) from exc aiohttp.client_exceptions.ClientConnectorError: Cannot connect to host www.biqudu.com:443 ssl:True [Too many open files] 

目前我能想到的方法是

• 修改linux 的最大文件打开数量限制
• 对 task 切片多次运行

但是这样解决都感觉太蠢了，请问有什么更好的方式吗？