我正在尝试对在 EC2 上的 Ubuntu 11.04 上的 tornado 2.4 上运行的应用程序进行故障排除。它似乎定期达到 100% CPU 并在该请求下停止几秒钟。
非常感谢您对此的任何帮助。
症状:
- top 在停止时显示 100% cpu。通常服务器的 CPU 利用率约为 30-60%。
- 它每 2-5 分钟停止一次请求。我已经检查过没有影响这一点的 cronjobs。
- 它会停止大约 2 到 9 秒。问题在重新启动龙卷风时消失,并随着龙卷风正常运行时间而恶化。服务器启动的时间越长,它停止的时间就越长。
- 出现问题的 Http 请求似乎没有任何模式。
- 有趣的是,日志中的下一个请求有时有时与停止持续时间匹配,有时则不匹配。例子:
00:00:00 GET /some/request () 00:00:09 GET /next/request (9000ms) 00:00:00 GET /some/request () 00:00:09 GET /next/request (1ms) # 9 seconds gap in requests is certainly not possible as clients are constantly polling.
- 数据库(mongodb)显示没有昂贵或大量的查询。没有页面错误。数据库在同一台机器上 - 本地磁盘。
- 与前几分钟相比,vmstat 显示读/写大小没有变化。
龙卷风在 nginx 后面运行。
在最有可能停止时发送 SIGINT,每次都会给出不同的堆栈跟踪。其中一些如下:
Traceback (most recent call last): File "chat/main.py", line 3396, in <module> main() File "chat/main.py", line 3392, in main tornado.ioloop.IOLoop.instance().start() File "/home/ubuntu/tornado/tornado/ioloop.py", line 515, in start self._run_callback(callback) File "/home/ubuntu/tornado/tornado/ioloop.py", line 370, in _run_callback callback() File "/home/ubuntu/tornado/tornado/stack_context.py", line 216, in wrapped callback(*args, **kwargs) File "/home/ubuntu/tornado/tornado/iostream.py", line 303, in wrapper callback(*args) File "/home/ubuntu/tornado/tornado/stack_context.py", line 216, in wrapped callback(*args, **kwargs) File "/home/ubuntu/tornado/tornado/httpserver.py", line 298, in _on_request_body self.request_callback(self._request) File "/home/ubuntu/tornado/tornado/web.py", line 1421, in __call__ handler = spec.handler_class(self, request, **spec.kwargs) File "/home/ubuntu/tornado/tornado/web.py", line 126, in __init__ application.ui_modules.iteritems()) File "/home/ubuntu/tornado/tornado/web.py", line 125, in <genexpr> self.ui["_modules"] = ObjectDict((n, self._ui_module(n, m)) for n, m in File "/home/ubuntu/tornado/tornado/web.py", line 1114, in _ui_module def _ui_module(self, name, module): KeyboardInterrupt Traceback (most recent call last): File "chat/main.py", line 3398, in <module> main() File "chat/main.py", line 3394, in main tornado.ioloop.IOLoop.instance().start() File "/home/ubuntu/tornado/tornado/ioloop.py", line 515, in start self._run_callback(callback) File "/home/ubuntu/tornado/tornado/ioloop.py", line 370, in _run_callback callback() File "/home/ubuntu/tornado/tornado/stack_context.py", line 216, in wrapped callback(*args, **kwargs) File "/home/ubuntu/tornado/tornado/iostream.py", line 303, in wrapper callback(*args) File "/home/ubuntu/tornado/tornado/stack_context.py", line 216, in wrapped callback(*args, **kwargs) File "/home/ubuntu/tornado/tornado/httpserver.py", line 285, in _on_headers self.request_callback(self._request) File "/home/ubuntu/tornado/tornado/web.py", line 1408, in __call__ transforms = [t(request) for t in self.transforms] File "/home/ubuntu/tornado/tornado/web.py", line 1811, in __init__ def __init__(self, request): KeyboardInterrupt Traceback (most recent call last): File "chat/main.py", line 3351, in <module> main() File "chat/main.py", line 3347, in main tornado.ioloop.IOLoop.instance().start() File "/home/ubuntu/tornado/tornado/ioloop.py", line 571, in start self._handlers[fd](fd, events) File "/home/ubuntu/tornado/tornado/stack_context.py", line 216, in wrapped callback(*args, **kwargs) File "/home/ubuntu/tornado/tornado/netutil.py", line 342, in accept_handler callback(connection, address) File "/home/ubuntu/tornado/tornado/netutil.py", line 237, in _handle_connection self.handle_stream(stream, address) File "/home/ubuntu/tornado/tornado/httpserver.py", line 156, in handle_stream self.no_keep_alive, self.xheaders, self.protocol) File "/home/ubuntu/tornado/tornado/httpserver.py", line 183, in __init__ self.stream.read_until(b("\r\n\r\n"), self._header_callback) File "/home/ubuntu/tornado/tornado/iostream.py", line 139, in read_until self._try_inline_read() File "/home/ubuntu/tornado/tornado/iostream.py", line 385, in _try_inline_read if self._read_to_buffer() == 0: File "/home/ubuntu/tornado/tornado/iostream.py", line 401, in _read_to_buffer chunk = self.read_from_fd() File "/home/ubuntu/tornado/tornado/iostream.py", line 632, in read_from_fd chunk = self.socket.recv(self.read_chunk_size) KeyboardInterrupt
非常感谢有关如何解决此问题的任何提示。
进一步的观察:
strace -p 在挂起期间显示空输出。
ltrace -p 在挂起期间仅显示大量 free() 调用: free(0x6fa70080) = free(0x1175f8060) = free(0x117a5c370) =